Steer-by-wire steering system having an off-axis steering system support column
The present disclosure relates to a steering system comprising a rotatable steering wheel hub; a steering system support column including an off-axis section and an aligned section that are connected by a connection portion. The steering wheel hub is rotatably mounted on the aligned section, while the off-axis section is axially spaced from the steering wheel hub. The steering system comprises a torque feedback device including an electric machine having a rotor and a stator, the rotor being attached to the steering wheel hub so as to be rotatable with the steering wheel hub about the axis of rotation, and the stator being non-rotatably fixed to the aligned section of the steering system support column.
1 . A steering system for a vehicle, comprising:
a steering wheel hub configured to be directly or indirectly connected with a steering wheel, the steering wheel hub being rotatable about an axis of rotation;
a steering system support column comprising:
an off-axis section having a first longitudinal axis that is off-set to the axis of rotation; and
an aligned section having a second longitudinal axis that corresponds to the axis of rotation, wherein the steering wheel hub is rotatably mounted on the aligned section, while the off-axis section is axially spaced from the steering wheel hub; and
a torque feedback device comprising an electric machine having a rotor and a stator, the rotor being attached to the steering wheel hub so as to be rotatable with the steering wheel hub about the axis of rotation, and the stator being non-rotatably fixed to the aligned section of the steering system support column,
wherein the rotor is an outer rotor and the stator is an inner stator,
wherein the off-axis section and the aligned section are connected by a connection portion, the connection portion extends transversally to both the first longitudinal axis and the second longitudinal axis.
2 . The steering system of claim 1 , wherein at least one of the off-axis section, the aligned section, or the connection portion is tubular, and has polygon shaped cross-section or circular cross-section.
3 . The steering system of claim 1 , wherein the steering system support column comprises an opening, which provides access to electrical connections.
4 . The steering system of claim 1 , further comprising an electronic control unit at least for at least one of controlling the torque feedback device or receiving and transmitting sensor information, the electronic control unit being arranged inside the off-axis section of the steering system support column.
5 . The steering system of claim 1 , further comprising a steering wheel rotation limiting device for limiting rotation of the steering wheel hub, the steering wheel rotation limiting device being attached to a non-rotatable component of the steering system support column via a base of the steering wheel rotation limiting device.
6 . The steering system of claim 5 , the steering wheel rotation limiting device further comprises a sliding element, and the steering wheel rotation limiting device engages the steering wheel hub via the sliding element.
7 . The steering system of claim 6 , wherein the base of the steering wheel rotation limiting device comprises two opposing end stop surfaces, and the sliding element is axially slidable parallel to the axis of rotation relative to the base and relative to the steering wheel hub between the two opposing end stop surfaces;
wherein a rotation of the steering wheel hub causes an axial movement of the sliding element, so that an abutment of the sliding element with one of the two end stop surfaces blocks the axial movement of the sliding element and the rotation of the steering wheel hub.
8 . The steering system of claim 6 , wherein the sliding element engages the steering wheel hub through a projection-and-groove engagement.
9 . The steering system of claim 8 , wherein the sliding element comprises a projection that engages a spiral groove formed on a circumferential surface of the steering wheel hub.
10 . The steering system of claim 5 , wherein the non-rotatable component is the off-axis section or the aligned section.
11 . The steering system of claim 5 , wherein the steering wheel rotation limiting device is arranged radially offset to the steering wheel hub.
12 . The steering system of claim 1 , wherein the first longitudinal axis is parallel to the axis of rotation.
13 . The steering system of claim 3 , wherein the opening of the steering system support column is arranged in the off-axis section or the connection portion.
14 . The steering system of claim 1 , wherein the steering system support column is attached to a vehicle body via a vehicle support column, wherein the off-axis section of the steering system support column is mounted in the vehicle support column so as to be translationally movable, non-rotatable and non-pivotable relative to the vehicle support column.
15 . The steering system of claim 14 , wherein the steering system support column forms an inner member of a tubular telescope arrangement and the vehicle support column forms an outer member of the tubular telescope arrangement.
16 . The steering system of claim 14 , wherein the vehicle support column is adjustable relative to the vehicle body by being at least one of pivotable or radially displaceable relative to the vehicle body.
17 . The steering system of claim 1 , further comprising auxiliary components which are arranged inside the aligned section of the steering system support column, the auxiliary components comprising in particular at least one of an airbag module, switchgear controls, a driver display arrangement, or a wiring harness.
18 . The steering system of claim 1 , wherein the aligned section of the steering system support column comprises a protruding flange portion that provides a first bearing surface for a first bearing arrangement arranged between the steering system support column and the steering wheel hub.
19 . The steering system of claim 1 , wherein the aligned section of the steering system support column comprises a circular ring-shaped portion that provides a second bearing surface for a second bearing arrangement arranged between the steering system support column and the steering wheel hub.