Wheel module for a motor vehicle

Abstract

A wheel module (14) for a motor vehicle (10), in particular a multi-track passenger motor vehicle, is provided, the wheel module having a wheel (18) which is rotatable about a center of rotation (38) and which serves to propel the motor vehicle, and the wheel module having a swing arm (24) which is attachable to a support frame (12) of the motor vehicle (10) so as to be articulated about a pivot axis (40), and wherein forces acting on the wheel (18) are supported on the support frame (12) by means of the swing arm, wherein the center of rotation (38) of the wheel (18) and the pivot axis (40) of the swing arm (24) are located on an imaginary radial line (42) starting from the center of rotation (38) of the wheel (18), wherein the radial line (42) extends at an angle α of 40°≤α≤35° relative to an X-Y plane (44) of the motor vehicle (10). By means of the angle α, the swing arm (24) can be articulated particularly close to the underlying surface (36) by means of a lever arm which facilitates the support of transverse forces acting on the wheel (18) with less material usage and less structural space requirement, thereby making a space-saving wheel module (14) possible.

Description

Technical Field

[0001] The invention relates to a wheel module for a motor vehicle, by means of which the motor vehicle can be steered and / or driven and / or braked and / or restrained by means of a spring / damper unit. Background Art

[0002] CN 206679065 U discloses a motor vehicle having a wheel module, wherein the wheels of the wheel module can be rotated through 90° about a vertical steering axis for parking the motor vehicle, even in confined parking spaces.

[0003] There is a constant need to be able to support the forces occurring in the wheel modules in a space-saving manner. Summary of the Invention

[0004] The object of the present invention is to identify measures which enable a space-saving wheel module.

[0005] This object is achieved by a wheel module having the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims and in the following description, each of which can represent an aspect of the invention either individually or in combination.

[0006] One embodiment provided relates to a wheel module for a motor vehicle, in particular a multi-track passenger motor vehicle, the wheel module having a wheel that can rotate about a center of rotation and is used to propel the motor vehicle, and the wheel module having a swing arm that can be attached to a support frame of the motor vehicle so as to be articulated about a pivot axis, and the forces acting on the wheel are supported on the support frame by means of the swing arm, wherein the center of rotation of the wheel and the pivot axis of the swing arm lie on an imaginary radial line starting from the center of rotation of the wheel, wherein the radial line extends at an angle of -40°≤α≤35° relative to the XY plane of the motor vehicle.

[0007] The mechanical support of the wheel via the swing arm is not arranged above the wheel in the Z direction, but rather as far downward as possible. If the swing arm is to be hinged to the support frame as close to the wheel circumference as possible, the pivot axis of the swing arm can be hinged at the edge of the wheel housing and / or preferably near the beam of the support frame, in the same height range as the wheel's center of rotation, particularly in the X direction. Forces acting on the wheel's contact point, particularly lateral forces arising during cornering, act together with the significantly lower lever arm when the swing arm is hinged above the wheel, thereby reducing bending moments about a bending axis extending substantially in the X direction. If the swing arm is hinged above the wheel in the Z direction, the lever arm effective for the supported joint forces will correspond to at least twice the wheel radius, while at the selected angle α, the effective lever arm can be less than twice the wheel radius. In the case of a negative angle α, when the swing arm is hinged below the XY plane including the wheel's center of rotation, the lever arm effective for the supported joint forces in the Y direction can always be less than the wheel's simple radius. The bending moments and lateral forces to be supported at the articulation of the swing arm during cornering can be significantly reduced, allowing the swing arm to be designed for lower loads. This reduces material usage, production costs, and the space required for the swing arm. Furthermore, load-bearing components of the motor vehicle, which are already present and have limited access to the vehicle interior, can be functionalized for the articulation of the swing arm, further reducing the number of components and space requirements. By means of the angle α, the swing arm can be articulated particularly close to the underlying surface, using a lever arm that facilitates the support of lateral forces acting on the wheel, while using less material and requiring less space. This allows for space-saving wheel modules.

[0008] The X direction is understood to mean a coordinate direction along the longitudinal axis of the motor vehicle when the wheel module is installed in the motor vehicle. When the motor vehicle is parked on a flat, horizontally extending bottom surface, the X direction extends substantially horizontally. The Y direction is understood to mean a coordinate direction along the transverse axis of the motor vehicle when the wheel module is installed in the motor vehicle. When the motor vehicle is parked on a flat, horizontally extending bottom surface, the Y direction extends substantially horizontally. The Z direction is understood to mean a coordinate direction along the vertical axis of the motor vehicle when the wheel module is installed in the motor vehicle. When the motor vehicle is parked on a flat, horizontally extending bottom surface, the Z direction extends substantially vertically. The X, Y, and Z directions are aligned orthogonally to one another. The X and Y directions may span an XY plane, which is arranged at a specific height in the Z direction in the horizontal plane of the motor vehicle when the motor vehicle is parked on a flat, horizontally extending bottom surface. The X and Z directions may span a substantially vertical XZ plane, which represents a longitudinal cross-section of the motor vehicle extending in the longitudinal direction of the motor vehicle at a specific position in the Y direction when the motor vehicle is parked on a flat, horizontally extending bottom surface. The Y and Z directions may span a substantially vertical YZ plane representing a cross-section of the motor vehicle extending in a transverse direction of the motor vehicle at a particular location in the X direction when the motor vehicle is parked on a flat, horizontally extending underlying surface.

[0009] In particular, the angle α is -30° ≤ α ≤ 20°, in particular -20° ≤ α ≤ 0°. As a result, the swing arm can be articulated particularly tightly in the region of the beam of the support frame. Consequently, the joint forces generated at the connection point of the swing arm can be transmitted to the support frame, in particular to the beam, via a correspondingly short lever arm.

[0010] Preferably, the distance d between the pivot axis and the underlying surface is 60 mm ≤ d ≤ 650 mm, particularly 80 mm ≤ d ≤ 590 mm, and preferably 100 mm ≤ d ≤ 260 mm. At this distance from the road surface, lateral forces acting on the swing arm can be supported by the support frame via a small lever arm. Furthermore, the distance from the ground is sufficiently great that the swing arm does not contact the ground, even if there are any bumps in the ground, such as potholes in the road.

[0011] Particularly preferably, a shock absorber is provided that acts on the swing arm and can be supported on the vehicle's support frame to dampen wheel vibrations caused by road irregularities. To dissipate the forces, the wheel can be supported on the vehicle's support frame solely via the swing arm and the shock absorber. The shock absorber can exert sufficient contact force on the wheel and dampen wheel vibrations caused by road bumps. Due to the articulated support of the swing arm, the swing arm can follow these wheel vibrations. The shock absorber's force direction is preferably aligned primarily in the Z direction. Thus, the shock absorber can primarily support forces generated in the Z direction, while the swing arm can primarily support forces generated in the X direction. An angle between the shock absorber's force direction and a radial line extending from the wheel's center of rotation to the swing arm's axis of rotation of greater than 45°, particularly greater than 60°, and preferably greater than 80°, reduces the forces generated in the shock absorber and effectively supports the swing arm, which is subject to low side loads, while using less material and requiring less space. This eliminates the need for and can reduce the need for additional supporting components, thus keeping space requirements and production costs low.

[0012] Specifically, a wheel carrier is rotatably mounted on a swing arm and attached to a wheel for steering the wheel, and an electrically operable steering actuator is attached to the swing arm and acts on the wheel carrier to rotate the wheel carrier. The steering actuator is attached to the swing arm and can use the swing arm to support forces that twist the wheel carrier. The steering actuator is not attached to the support frame, but rather is provided indirectly via the swing arm. Electrical wiring for controlling the steering actuator can track the relative movement of the steering actuator with respect to the support frame due to the pivoting movement of the swing arm, and for this purpose, the electrical wiring can have a suitable length and cable routing. The steering actuator can have a rotor coupled to a shaft. Specifically, the steering actuator can be arranged axially offset so that electromagnetic rotation of the rotor causes rotation of the wheel carrier attached to the shaft and the wheel connected to the wheel carrier. By axially offsetting the steering actuator relative to the rotational axis of the wheel carrier, the steering actuator can be arranged in a region within the wheel housing, which means that no installation space for the steering actuator has to be reserved outside the wheel housing.

[0013] Preferably, the swing arm comprises a lower support portion and an upper support portion disposed substantially above the lower support portion in the Z direction, for rotating the wheel about a Z-axis extending through the lower and upper support portions. The lower and upper support portions are connected to each other via a swing arm body formed by the swing arm, which extends in a particularly curved manner, so that the wheel can be locked in a steering position of at least 90°. At least one steering rod extends from the swing arm body for articulated connection to the support frame of the motor vehicle. For example, the swing arm body, which can be curved to conform to the contour of the wheel housing, creates a mounting space for the wheel, within which the wheel can rotate even at very large rotation angles exceeding 90°. Compared to a straight swing arm extending in the Z direction, the wheel does not strike the steering rod of the swing arm, and thus the wheel's steering angle is not blocked or limited by the steering rod. Due to the large steering angles that can be achieved, the motor vehicle can travel transversely to the direction of travel and / or turn on the spot. Consequently, the maneuverability of the motor vehicle can be significantly improved.

[0014] Particularly preferably, in order to enable the wheels to be locked in a rotational orientation of at least 90° relative to one another, the swing arm extends in an arcuate manner in the XY plane and in an arcuate manner in the YZ plane. This reliably prevents the wheels from colliding with the swing arm at very large steering angles.

[0015] In particular, the swing arm is rigid, in particular formed in one piece. The one-sided articulation of the swing arm makes it possible to avoid an articulated two-piece design of the swing arm by supporting the shock absorber acting on the wheel not on the swing arm, but on the rest of the motor vehicle, in particular directly or indirectly on the support frame. This increases the rigidity of the force support via the swing arm and keeps the number of components to a minimum.

[0016] One embodiment relates to a motor vehicle having a support frame and wheel modules supported on the support frame for steering the motor vehicle. The wheel modules can be designed and developed as described above, wherein each wheel module enables a steering angle of at least 90°. Due to the large steering angles that can be achieved, the motor vehicle can be driven transversely to the direction of travel and / or turn on the spot. By means of the angle α, the swing arms of the wheel modules can be articulated particularly close to the underlying surface, using lever arms that facilitate the absorption of transverse forces acting on the wheels, while using minimal material and requiring minimal installation space. This allows for a space-saving motor vehicle.

[0017] Preferably, the support frame includes a beam formed between the front wheel module in the X direction and the rear wheel module in the X direction, wherein the swing arm is articulated to the support frame at the height of the beam, in particular directly to the beam. This allows the swing arm to support the forces exerted on the wheels in the X direction with low component loads. In any case, the provided swing arm can easily support the forces and moments introduced by the swing arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the following, the present invention is described by way of example using preferred exemplary embodiments with reference to the accompanying drawings, wherein the features shown below can represent aspects of the present invention both individually and in combination. In the drawings:

[0019] Figure 1 : shows a schematic side view of a portion of an electrically driven motor vehicle,

[0020] Figure 2 : Shows the Figure 1 Schematic plan views of wheel modules of a motor vehicle with different steering angles,

[0021] Figure 3 : Shows the Figure 2 Schematic front view of the wheel module,

[0022] Figure 4 : Shows the Figure 1 a simplified detailed view of a first embodiment of a motor vehicle, and

[0023] Figure 5 : Shows the Figure 1 Simplified detailed illustration of a second embodiment of a motor vehicle. DETAILED DESCRIPTION

[0024] Motor vehicle 10 (in Figure 1 The motor vehicle 10 (shown only partially in the figure) can be configured as a zero-emission electric vehicle, for example, for urban mobility. The motor vehicle 10 has a support frame 12, which is typically substantially rectangular. Wheel modules 14, for example, supported directly or indirectly on the support frame, are attached to each of the support frame's corners. Between the wheel modules 14 located at the front and the wheel modules 14 located at the rear in the direction of travel, the support frame 12 has a beam 16 designed as a side member, which can define and / or support the lower edge of the entrance to the motor vehicle interior. The wheel modules 14 have rotatable wheels 18 that can be steered by means of steering actuators 20. Road bumps can be damped by shock absorbers 22 acting on the wheels 18. The shock absorbers 22 are supported at least indirectly on the support frame 12 above the wheels 18 to absorb forces acting on the wheels 18 in the Z direction. The wheels 18 are articulatedly supported on the support frame 12 via swing arms 24 to absorb forces acting on the wheels 18 in the X and Y directions. Due to the articulated connection of the swing arm 24 , the up and down movement of the wheel 18 , which is achieved by the shock absorber 22 , can be followed.

[0025] like Figure 2As shown in , the wheel 18 can rotate more than 90°. Thus, the motor vehicle 10 can also travel transversely to the direction of travel and / or rotate in place. For this purpose, in particular, each wheel 18 of the corresponding wheel module can be controlled and driven individually, so that a specific steering angle and a specific direction of rotation can be specified individually for each wheel 18, so as to realize a relatively large number of motor vehicles. In the exemplary embodiment shown, the wheel 18 can be deflected from the position for straight-ahead travel in one direction of rotation by at least 90°, in particular by approximately 95°, and by approximately 40° in the other direction of rotation. For this purpose, the swing arm 24 is sufficiently bent in the XY plane so that the wheel 18 does not hit the swing arm 24.

[0026] like Figure 3 As shown in FIG, the swing arm 24 may include a swing arm body 26, which is also curved in the YZ plane. At least one steering rod 28, hinged to the support frame 12, protrudes from this swing arm body. The swing arm body 26 includes an upper support portion 30 and a lower support portion 32, by means of which a wheel carrier 34 is rotatably mounted about a rotation axis extending generally in the Z direction. The wheel carrier 34 is connected to the wheel 18 and can be rotated by the steering actuator 20. The steering actuator 20 is offset relative to the rotation axis of the wheel carrier 34 and is coupled substantially axially parallel to the axis that rotates the wheel carrier, for example, via a gear pairing and / or a traction drive. The steering actuator 20 protrudes radially inward, which saves installation space and allows for easy attachment to the swing arm 24 outside the steering area of ​​the wheel 18, for example to prevent the steering actuator 20 from rotating together with the wheel carrier 34.

[0027] exist Figure 4 In the exemplary embodiment illustrated in FIG, with wheels 18 having tires of size 125 / 70R15, swing arm 24 is hinged to support frame 12 at a distance d of 590 mm from base plate 36. An imaginary radial line 42 extending from the center of rotation 38 of wheel 18 through a pivot axis 40 at the hinge point of swing arm 24 on support frame 12 is tilted at a mathematically positive angle α of 35° relative to an XY plane 44 and is hinged close to beam 16. The distance d from base plate 36 is so small that lateral forces acting in the Y direction on wheel 18 during cornering need only be supported by swing arm 24 on support frame 12 as a small bending moment.

[0028] exist Figure 5 In the exemplary embodiment of the motor vehicle 10 illustrated in FIG. Figure 4Compared to the exemplary embodiment of the motor vehicle 10 shown in FIG, the swing arm 24 is directly articulated to the beam 16 of the support frame 12 at a distance d=80 mm and a mathematically negative angle α of α=-40° to the radial line, thereby further reducing the bending moment supported by the swing arm 24 to the support frame 12 given sufficient ground clearance. The swing arm can also be articulated at a different angle α, for example at α=0°.

[0029] Reference Signs List

[0030] 10 Motor Vehicles

[0031] 12 Support frame

[0032] 14 wheel modules

[0033] 16 Liang

[0034] 18 rounds

[0035] 20 Steering actuator

[0036] 22 shock absorbers

[0037] 24 Swing Arm

[0038] 26 Swing arm body

[0039] 28 Steering rod

[0040] 30 Upper bearing

[0041] 32 lower support

[0042] 34 wheel carrier

[0043] 36 bottom surface

[0044] 38 Rotation Center

[0045] 40 Pivot axis

[0046] 42 radial lines

[0047] 44 XY plane

[0048] d distance

[0049] α angle

Claims

1. A wheel module for a motor vehicle (10), the wheel module comprising: a wheel (18) rotatable about a center of rotation (38) and configured to propel the motor vehicle, and a swing arm (24) which can be attached to a support frame (12) of the motor vehicle (10) so as to be articulated about a pivot axis (40) and by means of which forces acting on the wheel (18) are supported on the support frame (12), in, The rotation center (38) of the wheel (18) and the pivot axis (40) of the swing arm (24) are located on an imaginary radial line (42) starting from the rotation center (38) of the wheel (18), wherein the radial line (42) extends at an angle α of -40°≤α≤35° relative to an XY plane (44) of the motor vehicle (10), and the swing arm (24) has a lower support portion (32) and an upper support portion (30) arranged above the lower support portion (32) in the Z direction for the swing arm (24) to The wheel (18) rotates about a Z-axis extending through the lower support portion (32) and the upper support portion (30), wherein the lower support portion (32) and the upper support portion (30) are connected to each other via a swing arm body (26) formed by the swing arm (24) and extending in a curved manner to enable a steering angle of the wheel (18) of at least 90°, wherein at least one steering rod (28) extends from the swing arm body (26) for articulated connection to the support frame (12) of the motor vehicle (10).

2. The wheel module according to claim 1, characterized in that The angle α is -30°≤α≤20°.

3. The wheel module according to claim 1, characterized in that The angle α is -20°≤α≤0°.

4. The wheel module according to claim 1, characterized in that The distance d between the pivot axis (40) and the bottom surface (36) is 60 mm ≤ d ≤ 650 mm.

5. The wheel module according to claim 1, characterized in that The distance d between the pivot axis (40) and the bottom surface (36) is 80 mm ≤ d ≤ 590 mm.

6. The wheel module according to claim 1, characterized in that The distance d between the pivot axis (40) and the bottom surface (36) is 100 mm ≤ d ≤ 260 mm.

7. The wheel module according to any one of claims 1 to 6, characterized in that A shock absorber (22) is provided which acts on the swing arm (24) and can be supported on the support frame (12) of the motor vehicle (10) for damping vibrations of the wheel (18) caused by road irregularities, wherein, for the purpose of dissipating forces, the wheel (18) can be supported on the support frame (12) of the motor vehicle (10) solely via the swing arm (24) and the shock absorber (22).

8. The wheel module according to any one of claims 1 to 6, characterized in that A wheel carrier (34) rotatably mounted on the swing arm (24) and attached to the wheel (18) for steering the wheel (18) and an electrically operable steering actuator (20) attached to the swing arm (24) and acting on the wheel carrier (34) for rotating the wheel carrier (34) are provided.

9. Wheel module according to one of claims 1 to 6, characterized in that The swing arm (24) extends in an arcuate manner in both the XY plane (44) and the YZ plane to enable the wheel (18) to be turned at an angle of at least 90°.

10. The wheel module according to one of claims 1 to 6, characterized in that The swing arm (24) is rigidly formed in one piece.

11. A motor vehicle having a support frame (12) and a wheel module (14) according to any one of claims 1 to 10, supported on the support frame (12) for steering the motor vehicle (10), wherein: Each wheel module (14) enables the wheel (18) to be steered through an angle of at least 90°.

12. The motor vehicle according to claim 11, characterized in that The support frame (12) has a beam (16) formed between the front wheel module (14) in the X direction and the rear wheel module (14) in the X direction, wherein the swing arm (24) is hinged to the support frame (12) at the height of the beam (16).

13. The motor vehicle according to claim 12, characterized in that The swing arm is directly hinged to the beam (16).

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