ROTOR-HUB ASSEMBLY FOR MOTOR VEHICLES

Abstract

MOTOR VEHICLE ROTOR-HUB ASSEMBLY The present invention relates to an assembly (4) for a motor vehicle (2), comprising: - a brake rotor (6); - a hub (8) comprising a central axis (A) intended to coincide with an axis of a motor vehicle transmission shaft in its normal mounting position; notable in that the hub is formed with the brake rotor so as to constitute a single, monobloc piece, said hub forming a central cylindrical portion projecting from the brake rotor along the central axis, said central cylindrical portion being intended to engage with an inner ring (10.1) of a motor vehicle wheel bearing (10). (Figure to be published with the abbreviation: Figure 1)

Description

Title of the invention: ROTOR-HUB ASSEMBLY FOR A MOTOR VEHICLE Technical field

[0001] The present invention relates to the field of motor vehicles, more particularly the field of assemblies comprising a brake rotor and a hub for motor vehicles. Prior art

[0002] Each wheel of a motor vehicle is connected to a drive shaft which is fixed at its end to an assembly comprising a central hub and a brake rotor made of special cast iron.

[0003] The brake rotor, which can be a drum or a brake disc, is an essential component for stopping the vehicle. It rotates in conjunction with the central hub and provides braking through a set of pads and a caliper, which are actuated by pressurized oil. Conventionally, this rotor-hub assembly forms an assembly of two separate parts fixed by screwing. However, such a configuration presents challenges in terms of cost and manufacturing complexity.

[0004] Indeed, the supply of two separately manufactured parts (brake rotor and hub) entails additional costs, as does the machining of holes for the arrangement of the fixing screws, which complicates their manufacture and assembly. This complexity can lead to a considerable loss of time on automotive assembly lines, impacting productivity and overall production costs.

[0005] Published patent document EP 1 302 690 A2 discloses a one-piece assembly of a rotor and a hub for a motor vehicle wheel, comprising a bearing integrally inserted into a corresponding hole, said bearing comprising an inner ring intended to be directly connected to a transmission shaft of the motor vehicle.

[0006] Published patent document WO 2007 / 081074 A1 discloses a wheel disc and bearing assembly comprising an outer ring screwed to a suspension joint of a motor vehicle, and an inner ring extended into an orifice of the disc and engaged with a drive shaft of the motor vehicle.

[0007] However, the solutions proposed by the documents have room for improvement, as there is a need among these known solutions to further strengthen the mechanical connection of the drive shaft to the rotor-hub assembly, so as to better withstand the various forces during vehicle rolling, while optimizing the total mass of the assembly. In addition, the disclosed rotor-hub assemblies require a simplification of their assembly to motor vehicles. Statement of the invention

[0008] The present invention aims to overcome at least one of the drawbacks of the aforementioned state of the art. More particularly, the invention aims to propose a simple and efficient solution for efficiently and economically connecting a transmission shaft to a brake rotor.

[0009] To this end, the invention relates to an assembly for a motor vehicle, comprising: - a brake rotor; - a hub comprising a central axis intended to be merged with an axis of a motor vehicle transmission shaft, in the normal mounting position; remarkable in that the hub is formed with the brake rotor so as to constitute a single piece, said hub forming a central cylindrical part projecting from the brake rotor along the central axis, said central cylindrical part being intended to engage with an inner ring of a motor vehicle wheel bearing.

[0010] Preferably, the brake rotor comprises a brake disc for a motor vehicle.

[0011] According to one embodiment, the central cylindrical part comprises a through hole provided with a grooved internal face.

[0012] According to one embodiment, the central cylindrical portion comprises a substantially smooth outer face configured to engage by clamping with the inner ring of the corresponding bearing.

[0013] According to one embodiment, the central cylindrical part forms a cylindrical wall comprising a thickness presented between the grooved internal face and the external face, said thickness being between 2 and 15 mm.

[0014] According to one embodiment, the central cylindrical portion projects at least 20 mm from an inner friction surface of the brake rotor.

[0015] According to one embodiment, the brake rotor comprises a central cavity having a bottom recessed relative to the inner friction surface, the central cylindrical portion extending perpendicularly from said bottom over at least 30 mm.

[0016] The invention also relates to a motor vehicle comprising four transmission shafts connected to corresponding assemblies comprising, respectively, a brake rotor and a hub, remarkable in that at least one of the assemblies is according to the invention.

[0017] According to one embodiment, the transmission shaft comprises a distal portion which is splined and directly engaged with a splined internal face of a through hole in the central cylindrical portion of the corresponding assembly.

[0018] According to one embodiment, said motor vehicle comprises a suspension joint and a corresponding wheel bearing, said bearing comprising an outer ring fixed to an inner face of an opening of said joint.

[0019] According to one embodiment, the bearing comprises an inner ring mounted tightly with an external face of the central cylindrical part of the assembly.

[0020] The measures of the invention are advantageous in that the single-piece assembly combining the brake rotor and the hub makes it possible to facilitate the manufacturing and assembly operations on the motor vehicle, thus ensuring considerable savings in costs and time on the motor vehicle assembly lines.

[0021] In addition, the hub forming a central cylindrical part projecting from the rotor, makes it possible to increase the connection surface with the transmission shaft. This makes it possible to improve the mechanical strength of the assembly by guaranteeing better resistance to the various rolling forces of the motor vehicle, which also makes it possible to increase the service life of the wheel bearing used and thus to simplify the latter. Brief description of the drawings

[0022] [Fig-1] represents an exploded and perspective view of an assembly for a motor vehicle according to the invention, as well as a corresponding wheel bearing, suspension joint and brake caliper.

[0023] [Fig.2] illustrates a sectional view along a central axis of an assembly of the assembly with the bearing and the articulation of [Fig.l]. Detailed description

[0024] [Fig.l] represents an exploded and perspective view of an assembly 4 for a motor vehicle 2 according to the invention, as well as a corresponding wheel bearing 10, a suspension joint 12 and a brake caliper 14.

[0025] The motor vehicle 2 comprises a transmission shaft (not shown) comprising a main axis merged with a central axis A and intended to successively pass through an opening 12.1 of the articulation, the bearing 10 and the assembly 4 according to the invention to be fixed to the latter.

[0026] The assembly 4 comprises a brake rotor 6 preferably corresponding to a brake disc 6, and may alternatively be a brake drum. The rotor 6 is configured to cooperate with two brake pads 14.1 of the caliper 14. The assembly 4 further comprises a hub 8 formed with the brake rotor so as to constitute a single piece. The assembly 4 is preferably obtained from cast iron.

[0027] Advantageously, the assembly 4 is compact and rigid, and does not require any screws between the hub 8 and the brake rotor 6.

[0028] The hub 8 preferably forms a central cylindrical part 8 projecting from the rotor 6 along the central axis A, and intended to engage with an inner ring 10.1 of the bearing 10, in the normal mounting position on the motor vehicle 2, as illustrated in [Fig.2].

[0029] [Fig.2] illustrates a sectional view along the central axis A of an assembly of the set 4 with the bearing 10 and the articulation 12.

[0030] It can be seen that the hub 8 is coupled to the bearing 10 inside the vehicle 2, and is thus connected to the articulation 12. In this respect, the bearing 10 comprises an outer ring 10.2 which is directly and exclusively mounted on the articulation 12 of the suspension, and precisely fixed to an inner face 12.2 of the opening 12.1.

[0031] Preferably, the central cylindrical part 8 comprises an external face 8.1 which is substantially smooth and tightly mounted with the inner ring 10.1 of the corresponding bearing.

[0032] The central cylindrical part 8 comprises a through hole 8.2 provided with a grooved internal face 8.3. In this configuration, the transmission shaft (not shown) comprises a grooved distal portion which is directly and exclusively engaged with the grooved internal face 8.3 of the assembly 4. Thus, the transmission shaft does not come into contact with the bearing 10.

[0033] Advantageously, the exclusive engagement of the transmission shaft with the grooved internal face 8.3 directly formed in the assembly 4, makes it possible to further reinforce the assembly and thus guarantee better mechanical resistance to forces, without requiring reinforcement of the rings 10.1, 10.2 of the bearings.

[0034] Preferably, the central cylindrical part 8 forms a cylindrical wall comprising a thickness E presented between the grooved internal face 8.3 and the external face 8.1, said thickness being equal to at most 30 mm, and preferably between 2 and 15 mm, and is more preferably equal to approximately 5 mm (±2 mm). The through hole 8.2 comprises a diameter D between 10 mm and 50 mm.

[0035] The rotor 6 preferably comprises a central cavity 7 comprising a bottom 7.1 pressed in relative to an inner friction surface 6.1 of said rotor 6, the latter being arranged transversely towards the inside of the motor vehicle 2, as opposed to an outer friction face 6.2 arranged transversely opposite a corresponding wheel of the vehicle 2.

[0036] The central cylindrical part 8 extends perpendicularly from the bottom 7.1 on a length L equal to at least 30 mm along the central axis A, and extending over at most 150 mm from said bottom 7.1.

[0037] The central cylindrical part 8 projects at least 20 mm from the inner friction surface 6.1. Thus, the cavity 7 has a depression of at least 10 mm between the bottom 7.1 and the friction face 6.1.

[0038] Advantageously, the transverse extent of the central cylindrical part 8 from the rotor makes it possible to considerably increase the connection surface with the transmission shaft. This makes it possible to improve the mechanical strength of the assembly by guaranteeing better resistance to the various rolling forces of the motor vehicle.

Claims

Claims

1. Assembly (4) for a motor vehicle (2), comprising: - a brake rotor (6); - a hub (8) comprising a central axis (A) intended to be merged with an axis of a motor vehicle transmission shaft (2), in the normal mounting position; characterized in that the hub (8) is formed with the brake rotor (6) so as to constitute a single piece, said hub (8) forming a central cylindrical part (8) projecting from the brake rotor (6) along the central axis (A), said central cylindrical part (8) being intended to engage with an inner ring (10.1) of a wheel bearing (10) of a motor vehicle (2).

2. An assembly (4) according to claim 1, wherein the central cylindrical portion (8) comprises a through hole (8.2) provided with a grooved internal face (8.3).

3. Assembly (4) according to one of claims 1 and 2, in which the central cylindrical part (8) comprises an external face (8.1) which is substantially smooth and configured to engage by clamping with the inner ring (10.1) of the corresponding bearing (10).

4. Assembly (4) according to claims 2 and 3, in which the central cylindrical part (8) forms a cylindrical wall comprising a thickness (E) presented between the grooved internal face (8.3) and the external face (8.1), said thickness (E) being between 2 and 15 mm

5. Assembly (4) according to one of claims 1 to 4, in which the central cylindrical part (8) projects at least 20 mm from an inner friction surface (6.1) of the brake rotor (6).

6. An assembly (4) according to claim 5, wherein the brake rotor (6) comprises a central cavity (7) having a bottom (7.1) recessed relative to the inner friction surface (6.1), the central cylindrical portion (8) extending perpendicularly from said bottom (7.1) by at least 30 mm.

7. Motor vehicle (2) comprising four transmission shafts connected to corresponding assemblies (4) comprising, respectively, a brake rotor (6) and a hub (8), characterized in that at least one of the assemblies (4) is according to one of claims 1 to 6.

8. A motor vehicle (2) according to claim 7, wherein the shaft of transmission comprises a distal portion grooved and directly engaged with a grooved internal face (8.3) of a through hole (8.2) of the central cylindrical part (8) of the corresponding assembly (4).

9. Motor vehicle (2) according to one of claims 7 and 8, comprising a suspension joint (12) and a corresponding wheel bearing (10), said bearing (10) comprising an outer ring (10.2) fixed to an inner face (12.2) of an opening (12.2) of said joint (12).

10. Motor vehicle (2) according to claim 9, wherein the bearing (10) comprises an inner ring (10.1) mounted tightly with an outer face (8.1) of the central cylindrical part (8) of the assembly (4).