MOTOR WHEEL FOR AUTOMOBILE WITH BRAKE DUST PARTICLE CAPTURE

Abstract

MOTOR WHEEL FOR MOTOR VEHICLE WITH BRAKE DUST PARTICLE CAPTURE The present invention relates to a wheel (4) of a motor vehicle (2), comprising: - an electric motor for driving the wheel in rotation, said electric motor comprising a stator (8) intended to be fixedly connected to a suspension axle of a motor vehicle, and a rotor (10) mounted for rotation relative to the stator and comprising an axis of rotation, said stator being arranged radially internally within said rotor; and - a braking device (16) capable of braking the rotor, notable in that the stator comprises at least one permanent magnet (22) disposed on an external circumferential face (8.1) of said stator, said at least one permanent magnet comprising an external face (22.1) provided with a cavity (24) opening radially outwards towards the rotor, said cavity being configured to capture and retain brake dust particles (26) originating from the braking device. (Figure to be published with the abbreviation: Figure 3).

Description

Title of the invention: WHEEL MOTOR FOR AUTOMOBILE WITH CAPTURE BRAKE DUST PARTICLES technical field

[0001] The present invention relates to the field of motor vehicles, more particularly to the field of capturing brake dust particles from motor vehicles. Previous technique

[0002] Motor vehicle braking systems emit microparticles that are harmful to health, resulting in particular from the abrasion of brake linings and discs. These microparticles can cause various serious problems such as respiratory irritation and cardiovascular diseases.

[0003] To this end, the reduction of fine particle emissions, in particular those from braking systems, has become a crucial issue for car manufacturers.

[0004] Although solutions such as brake dust extraction systems connected to brake linings exist to collect these harmful microparticles, they are not suitable for vehicles equipped with electric traction motors, commonly referred to as "wheel motors", due to space constraints and high costs.

[0005] US patent document 2014 / 0159468 Al discloses a vehicle with a wheel motor where the rim is integrated into the rotor of the electric motor, accompanied by a brake drum equipped with magnets for capturing brake particles.

[0006] However, the solution proposed by the document has room for improvement, in particular to further increase the efficiency of capturing brake dust particles and limit their spread to the environment. Description of the invention

[0007] The present invention aims to overcome at least one of the drawbacks of the aforementioned prior art. More particularly, the invention aims to provide a simple, efficient, and economical solution for effectively capturing and retaining brake dust particles from a braking device of a wheel of a motor vehicle equipped with an electric drive motor for said wheel.

[0008] To this end, the invention relates to a motor vehicle wheel, comprising: - an electric motor for driving the rotating wheel, said electric motor comprising a stator intended to be fixedly connected to a suspension axle of a motor vehicle, and a rotor mounted to rotate relative to the stator and comprising an axle of rotation, said stator being arranged radially internally within said rotor; and - a braking device capable of braking the rotor, notable in that the stator comprises at least one permanent magnet disposed on an external circumferential face of said stator, said at least one permanent magnet comprising an external face having a cavity opening radially externally towards the rotor, said cavity being configured to capture and retain brake dust particles from the braking device.

[0009] According to one embodiment, the braking device includes a brake caliper having brake linings intended to engage and brake the rotor, the cavity being arranged opposite said brake caliper.

[0010] According to one embodiment, the cavity comprises a radial depth corresponding to at least 70% of a total radial thickness of at least one permanent magnet.

[0011] According to one embodiment, the cavity forms a circumferential groove comprising two parallel internal lateral faces, one of said two internal lateral faces being aligned with an external lateral face of the brake caliper, along the axis of rotation.

[0012] According to one embodiment, said motor vehicle wheel further comprising a brake disc mounted on the rotor and on a rim of said wheel.

[0013] According to one embodiment, the cavity has an axial width measured along the axis of rotation of the wheel, which is greater than an axial thickness of the brake disc.

[0014] According to one embodiment, the at least one permanent magnet comprises at least two permanent magnets arranged on the external circumferential face of said stator, and arranged symmetrically with respect to the axis of rotation.

[0015] According to one embodiment, the at least one permanent magnet consists of four permanent magnets distributed uniformly on the outer circumferential face of the stator.

[0016] The invention also relates to a motor vehicle, remarkable in that it includes at least one wheel according to the invention.

[0017] The measures of the invention are advantageous in that the arrangement of the cavities of the permanent magnets all around the stator and opposite the rotor at the level of the braking device makes it possible to attract and retain a large quantity of brake dust particles, and this without clogging the wheel of the motor vehicle.

[0018] Furthermore, the shape of the cavities allows the magnets to serve as storage reservoirs for harmful particles, preventing their spread into the environment external to the wheel of the motor vehicle and thus promoting compliance with current ecological constraints. Brief description of the drawings

[0019] [Fig.1] represents a perspective view of a wheel of a motor vehicle according to the invention;

[0020] [Fig.2] illustrates a cross-sectional view along a longitudinal axis AA of the wheel of the [Fig.1], showing two permanent magnets with a cavity positioned opposite a brake caliper;

[0021] [Fig.3] represents an enlarged view of the cavity near the brake caliper at the [Fig.2], schematically illustrating the capture and retention of brake dust particles emitted by said brake caliper;

[0022] [Fig.4] illustrates a cross-sectional view along a cutting plane passing through the wheel of the [Fig.2] transverse to an axis of rotation of said wheel. Detailed description

[0023] In this description, the axial direction is along the axis of rotation of a motor vehicle wheel. The term "inner" refers to the part near the inner side of the motor vehicle along this axial direction, while the term "outer" refers to the opposite part of the motor vehicle in the same direction. The terms "inner" and "outer" refer to the radial direction, perpendicular to the axis of rotation (axial direction).

[0024] Fig. 1 represents a perspective view of a wheel 4 of a motor vehicle 2 according to the invention.

[0025] The wheel 4 is of the wheel motor type, comprising an electric traction motor 6 for driving said wheel 4 in rotation, comprising a stator 8 intended to be fixedly connected to a suspension axle (coincided with an axis of rotation R) of the motor vehicle 2, and a rotor 10 coupled in rotation with the stator 8 and comprising the axis of rotation R.

[0026] In this configuration, the stator 8 is arranged radially inside the rotor 10. The latter is preferably fixed to a rim 12 on which a tire 14 of the wheel 4 is mounted.

[0027] The wheel 4 also includes a braking device 16 suitable for braking the rotation of the rotor 10, and therefore that of the motor vehicle 2. The device 16 may include a drum brake and / or a disc brake.

[0028] Preferably, the braking device 16 corresponds to a disc brake comprising a brake caliper 18 fixed to the stator 8 and a brake disc 20 fixed to the rotor 10 and to the rim 12. In this regard, the braking device 16 includes brake linings (not shown) intended to engage and brake the rotor 10.

[0029] Advantageously, the present invention proposes to capture harmful particles of brake dust from the braking device 16, by means of at least one permanent magnet 22 of the stator 8. Preferably, the latter has several permanent magnets 22 allowing in part the rotation of the rotor 10 by interaction of magnetic fields.

[0030] Advantageously, the present invention proposes to use the permanent magnets 22 of the stator 8 to maximize the capture and retention of harmful particles. In this regard, each magnet 22 is provided with a cavity 24, the shape and function of which will be detailed later in this description.

[0031] Fig. 2 illustrates a cross-sectional view along a longitudinal axis AA of the wheel of Fig. 1 passing through two permanent magnets 22.

[0032] It can be seen that each magnet 22 is arranged on an external circumferential face 8.1 of the stator 8, and extends axially along the axis of rotation R so that an external face 22.1 of the magnet 22 is opposite a total axial extent of the rotor 10.

[0033] Preferably, each cavity 24 opens radially outwards towards the rotor 10, and more preferably towards the axial position of the braking device 16. In this configuration, the cavities 24 are arranged all around the stator 8 so as to capture the particles that can propagate circumferentially because of the rotation of the rotor 10 and the disc 20.

[0034] Fig. 3 represents an enlarged view of the cavity 24 near the brake caliper 18 in Fig. 2, schematically illustrating the capture and retention of brake dust particles 26 emitted by the braking device 16.

[0035] Dashed arrows illustrate the movement of the particles 26 towards the cavity 24. Indeed, the said particles 26 being ferromagnetic, they are captured by the magnet 22, and more precisely by the cavity 24 which is advantageously located as close as possible to the braking device 16.

[0036] Preferably, the cavity 24 comprises a radial depth p corresponding to at least 70% of a total radial thickness E of the corresponding permanent magnet 22. More preferably, the depth p corresponds to approximately 90% of the thickness E, thereby maximizing the storage space for the particles 26 in the cavity 22.

[0037] The cavity 24 forms a circumferential groove opposite the stator 8; it comprises two parallel internal lateral faces 24.1, 24.2, one of said two internal lateral faces 24.1 being preferably aligned with an external lateral face 18.1 of the brake caliper 18, along the axis of rotation. This is the lateral face 24.1 on the side axially external to the wheel 4.

[0038] Preferably, the cavity 24 has an axial width w measured between the two lateral faces 24.1 and 24.2, said width w being greater than an axial thickness L of the brake disc 20. More preferably, the width w is equal to about half of a total axial width of the brake caliper 18, measured between these two lateral faces 18.1 and 18.2.

[0039] Advantageously, the shape and arrangement of the cavity 24 in the wheel 4 of the motor vehicle 2, allows for optimization of the capture and retention of particles 26.

[0040] Fig. 4 illustrates a cross-sectional view along a cutting plane passing through wheel 4 of Fig. 2 transversely to the axis of rotation R.

[0041] Preferably, the permanent magnets 22 can be in a number between 2 and 20, and more preferably between 2 and 8, and even more preferably in a number equal to 4, distributed uniformly around the stator 8 and symmetrically with respect to the axis of rotation R.

[0042] Advantageously, the cavities 24 extend around the stator 8 so as to cover at least 50% of the total circumferential area of ​​said stator 8. This coverage can extend up to 100% of said circumferential area. More preferably, the cavities 24 circumferentially cover the stator 8 to a extent of approximately 70% (±10%).

[0043] Advantageously, the wheel 4 of the present invention makes it possible to ensure efficient capture and retention of harmful brake dust particles, without obstructing said wheel 4. Thus, the invention also makes it possible to free up sufficient space to, for example, install traction electric accumulators, resulting in an increase in the range of the motor vehicle 2.

Claims

Demands

1. Wheel (4) of a motor vehicle (2), comprising: - an electric motor (6) for driving the wheel (4) in rotation, said electric motor (6) comprising a stator (8) intended to be fixedly connected to a suspension axle of a motor vehicle (2), and a rotor (10) mounted for rotation relative to the stator and comprising an axis of rotation (R), said stator (8) being arranged radially internally within said rotor (10); and - a braking device (16) capable of braking the rotor (10), characterized in that the stator (8) comprises at least one permanent magnet (22) disposed on an external circumferential face (8.1) of said stator (8), said at least one permanent magnet (22) comprising an external face (22.1) provided with a cavity (24) opening radially outwards towards the rotor (10), said cavity (24) being configured to capture and retain brake dust particles (26) from the braking device (16).

2. Wheel (4) according to claim 1, wherein the braking device (16) comprises a brake caliper (18) having brake linings intended to engage and brake the rotor (10), the cavity (24) being disposed opposite said brake caliper (18).

3. Wheel (4) according to any one of claims 1 and 2, wherein the cavity (24) extends around the stator (8) so as to cover at least 50% of a total circumferential extent of said stator (8).

4. Wheel (4) according to any one of claims 1 to 3, wherein the cavity (24) comprises a radial depth (p) corresponding to at least 70% of a total radial thickness (E) of at least one permanent magnet (22).

5. Wheel (4) according to any one of claims 1 to 4 and according to claim 2, in which the cavity (24) forms a circumferential groove comprising two parallel internal lateral faces (24.1, 24.2), one (24.1) of said two internal lateral faces (24.1, 24.2) being aligned with an external lateral face (18.1) of the brake caliper (18), along the axis of rotation (R).

6. Wheel (4) according to any one of claims 1 to 5, further comprising a brake disc (20) mounted on the rotor (10) and on a rim (12) of said wheel (4).

7. Wheel (4) according to claim 6, in which the cavity (24) has an axial width (w) measured along the axis of rotation (R) of the wheel, which is greater than an axial thickness (L) of the brake disc (20).

8. Wheel (4) according to any one of claims 1 to 7, wherein the at least one permanent magnet (22) comprises at least two permanent magnets (22) arranged on the outer circumferential face (8.1) of said stator (8), and arranged symmetrically with respect to the axis of rotation (R).

9. Wheel (4) according to any one of claims 1 to 8, wherein the at least one permanent magnet (22) consists of four permanent magnets (22) distributed uniformly over the outer circumferential face (8.1) of the stator (8).

10. Motor vehicle (2), characterized in that it comprises at least one wheel (4) according to any one of claims 1 to 9.

Images