STEER-BY-WIRE STEERING COLUMN

Abstract

A steer-by-wire steering column comprises a single column shroud extending longitudinally. The steering column also comprises a single steering shaft extending longitudinally and located at least partially within the single column shroud. The steering column further comprises an electric steer-by-wire actuator, located at least partially within the single column shroud and surrounding the single steering shaft to provide resistance to the single steering shaft.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 525,067, filed July 5, 2023, the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] This disclosure relates to vehicle steering systems and, more particularly, to a steer-by-wire steering column. BACKGROUND

[0003] A vehicle, such as a car, truck, SUV, crossover, minivan, watercraft, aircraft, off-road vehicle, recreational vehicle, or other suitable vehicle, typically includes a steering system with a steering column. For many years, steering columns have included one or more shell housings containing a steering shaft assembly physically connected to a rack or other device that actuates the road wheels. Advances in electrical technology have led to developments that eliminate the continuous physical connection between the steering input device and the road wheels. Such a steering system is called a steer-by-wire steering system. Another electrical system is called electric power steering (EPS), where power is provided at the column or rack, for example.

[0004] Previous steering systems, whether steer-by-wire or otherwise, that incorporate manual tilt and axial control require two or more sleeves and two or more steering shafts (e.g., upper and lower sleeves and shafts). As with any system, it is typically advantageous to reduce the number of components and the complexity of the system.

[0005] In addition to the number of components required by existing steering columns for steer-by-wire type systems, the steering wheel actuator, which provides resistance, feedback, and support to a steering shaft, is often mounted on the steering column at an angle or even perpendicular to the longitudinal axis of the steering column, requiring additional space and complicating the overall packaging effort. SUMMARY OF REVELATION

[0006] According to one aspect of the disclosure, a steer-by-wire steering column includes a single column shell extending in a longitudinal direction. The steering column also includes a single steering shaft extending in the longitudinal direction and at least partially housed within the single column shell. The steering column further includes an electric steer-by-wire actuator disposed at least partially within the single column shell and surrounding the single steering shaft to provide resistance to the single steering shaft.

[0007] According to another aspect of the disclosure, a steer-by-wire steering column includes a single column shell extending in a longitudinal direction, the single column shell defining a first pair of slots for receiving an adjustment pin of a manual adjustment assembly therethrough, wherein a first position of the adjustment pin within the first pair of slots defines a fully axially inner position of the single column shell and the single steering shaft, and a second position of the adjustment pin within the first pair of slots defines a fully axially outer position of the single column shell and the single steering shaft. The steering column also includes a single steering shaft extending in the longitudinal direction and at least partially housed within the single column shell.The steering column further includes an electric steer-by-wire actuator disposed at least partially within the single column shell and surrounding the single steering shaft to provide resistance to the single steering shaft. The electric steer-by-wire actuator includes a rotor structure operatively coupled to a radially outer surface of the single steering shaft. The electric actuator also includes a motor stator at least partially surrounding the rotor structure.The steering column also includes a housing end structure operatively coupled to an open end of the single column shell, the housing end structure defining a second pair of slots for receiving at least one component extending from a vehicle structure to which the single column shell and the housing end structure move relative, wherein a first position of the at least one component within the second pair of slots defines the fully axially inward position of the single column shell and the single steering shaft, and a second position of the at least one component within the second pair of slots defines a fully axially outward position of the single column shell and the single steering shaft.

[0008] These and other aspects of the present disclosure are disclosed in the following detailed description of the embodiments, the appended claims, and the accompanying figures. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, in accordance with common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features have been arbitrarily expanded or reduced for the sake of clarity. Fig. 1 schematically illustrates a vehicle steering system; Fig. 2 is a first perspective view of a steer-by-wire steering column; Fig. 3 is a second perspective view of the steer-by-wire steering column; Fig. 4 is a side elevation of the steer-by-wire steering column in a fully axially outward position; Fig. 5 is a side elevation of the steer-by-wire steering column in a fully axially inward position; Fig. 6 is a sectional side elevation view of the steer-by-wire steering column; Fig. 7 is a side elevational view of an energy absorption belt assembly for the steer-by-wire steering column; Fig. 8 is a perspective view of the energy absorption belt assembly; and Fig. 9 is a perspective, partially transparent view of the energy absorption belt assembly. DETAILED DESCRIPTION

[0010] The following discussion is directed to various embodiments of the disclosure. The embodiments disclosed herein should not be interpreted or otherwise used to limit the scope of the disclosure, including the claims. Furthermore, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is intended only to illustrate that embodiment and is not intended to imply that the scope of the disclosure, including the claims, is limited to that embodiment.

[0011] The embodiments disclosed herein may benefit various types of steering systems in a vehicle, such as a car, truck, SUV, crossover, minivan, watercraft, aircraft, off-road vehicle, recreational vehicle, or other suitable vehicle. In particular, the embodiments relate to a steer-by-wire steering column with manual adjustment capability, wherein the steering column advantageously eliminates steering column parts compared to a conventional steering column, which typically requires two or more sleeves and two or more steering shaft components.

[0012] With reference to Fig. 1, the steering column assembly is generally designated by reference numeral 10. The steering column assembly includes a steering wheel 12, wherein a driver can provide steering input by rotating the steering wheel 12. The steering column assembly 10 is a steer-by-wire type steering system. Therefore, the steering column assembly 10 does not include a continuous mechanical connection between the steering wheel 12 and an output gear and rack 14 that effect physical adjustment of road wheels 16 for steering maneuvers. Even with prior steer-by-wire systems, multiple steering shafts and / or multiple steering column shells were required to operatively couple the steering wheel 12 to another component, such as an actuator or the like. However, the embodiments disclosed herein reduce the number of primary components required by the steering column assembly 10.

[0013] Now with reference to the Fig. 2 and Fig. 3, the steer-by-wire steering column assembly 10 is shown in more detail. The steer-by-wire steering column assembly 10 is manually adjustable and includes a single steering column shell 20 that at least partially receives a single steering shaft 22. Therefore, it should be understood that the entire steering column shell assembly is limited to the single shell 20 and that the single shell 20 receives at least a portion of the single steering shaft 22. Therefore, the entire steering shaft assembly is limited to a single steering shaft 22 and is not a composite plurality of segments that form the steering shaft assembly. The single steering shaft 22 has an end 24 extending from the single shell 20 in a generally rearward direction of the vehicle. The end 24 extending from the single shell 20 is configured to have a steering input device—such as a steering wheel—operably coupled thereto.

[0014] The steer-by-wire steering column assembly 10 also includes a manual adjustment assembly 30 that provides a user with the ability to manually adjust an axial and / or tilt position of the steer-by-wire steering column assembly 10. The term “axial movement” refers to movement of the single sleeve 20 in a direction substantially parallel to a longitudinal axis A of the steer-by-wire steering column assembly 10. The term “tilt movement” refers to movement of the single sleeve 20 in a substantially upward and downward direction relative to the longitudinal axis A of the steer-by-wire steering column assembly 10. The manual adjustment assembly 30 includes an adjustment lever 32. Upon rotation of the adjustment lever 32, one or more cams 34 and / or other components move to an unlocked position, allowing all or a portion of the steer-by-wire steering column assembly 10 to be manually adjusted.

[0015] The single shell 20 defines a pair of slots 40 that extend generally in a longitudinal direction of the steer-by-wire steering column assembly 10. The pair of slots 40 may be defined within a pair of rails 42 that extend from the main body 44 of the single shell 20, as illustrated. The pair of slots 40 allows an adjustment pin 46 to extend through each of the slots 40 and connect to components of the manual adjustment assembly 30. During axial movement of the single shell 20, the adjustment pin 46 slides within the slots 40 between a fully axial "outer" position ( Fig. 4) and a completely axial “inner” position ( Fig. 5). The fully axially outer position corresponds to a rearmost position in a vehicle direction (i.e., the position closest to the operator position). The fully axially inner position corresponds to a forwardmost position in a vehicle direction (i.e., the position farthest from the operator position).

[0016] Now with reference to Fig. 6 and with further reference to the Fig. 2-5, the steer-by-wire steering column assembly 10 also includes a housing end structure 50 operatively coupled to the single shell 20. The housing end structure 50 is attached to an open end 52 of the single shell 20 to close the single shell 20 and provide a location for mounting a lower bearing 54. In some embodiments, the lower bearing 54 is press-fitted into the housing end structure 50. The single steering shaft 22 is supported by the lower bearing 54 and an upper bearing 56. In the illustrated perspective, the lower bearing 54 is located on the left side of the single steering shaft 22, and the upper bearing 56 is located on the right side of the single steering shaft 22. Supporting the single steering shaft 22 by two bearings provides a stable structure for creating a rigid steering column construction assembly.

[0017] The housing end structure 50 defines a pair of slots 58. The pair of slots 58 enables operative coupling between the housing end structure 50 and a vehicle structure 60, such as a mounting bracket. Components extending from the vehicle structure 60 extend through each of the slots 58. As with the adjustment pin 46 in the slots 40 of the single shell 20, the components of the vehicle structure 60 slide within the slots 58 of the housing end structure 50 during axial movement of the steer-by-wire steering column assembly 10 between a fully axially outward position ( Fig. 4) and a completely axially inner position ( Fig. 5). As shown, the fully axially inner position leaves space between the elements (i.e., components and adjustment pin) located within the slots 40, 58 and respective ends of the slots 70, 72, as well as Fig. 5. In other words, the fully axially outward position of the adjustment pin 46 is at or near a first end of the first pair of slots 48, and the fully axially inward position of the adjustment pin 46 is spaced from a second end of the first pair of slots 48. Likewise, the fully axially outward position of the at least one component within the second pair of slots 58 is at or near a first end of the second pair of slots 50, and the fully axially inward position of the at least one component is spaced from a second end of the second pair of slots 50. This provides space for the steer-by-wire steering column assembly 10, specifically the single shell 20 and coupled components, to traverse a crash stroke range. The crash stroke range enables energy absorption during an impact event.

[0018] Fig. 6 is a partial cross-sectional view illustrating an interior cavity 80 of the single shell 20. One or more magnets forming a rotor structure assembly 82 are mounted on a radially outer surface of the single steering shaft 22. Copper windings of a motor stator 84 are mounted on an interior wall 86 of the single shell 20 and do not rotate. The motor stator 84 at least partially surrounds the rotor structure assembly 82. The magnets of the rotor assembly 82 rotate with the single steering shaft 22. The entire electrical steer-by-wire device (e.g., motor plus additional components) may be referred to as an "emulator." The emulator resists rotation of the single steering shaft 22 to provide steering feedback to the driver and assists steering inputs to adjust the amount of effort required by the driver.The emulator is mounted in a manner in which the emulator directly surrounds the single steering shaft 22 to eliminate the need for a gearbox by utilizing a direct drive system. The assembly also includes one or more rotational position sensors 90 to detect the angular rotational position of the single steering shaft 22 and one or more travel stop limiters 92 to define travel limits for the movement of the single steering shaft 22. It is noted that the motor stator 84 and the single shell 20 remain rotationally fixed relative to the single steering shaft 22 during operation.

[0019] The Fig.7-9 illustrate an energy absorption assembly 100 for the steer-by-wire steering column assembly 10. The energy absorption assembly 100 includes an energy absorption belt 102 coupled to an outer surface of the single column shell 20 and having a plurality of teeth 104. The energy absorption assembly 100 also includes a pivotable member 106 having one or more teeth engageable with the teeth 104 of the energy absorption belt 102 to move the energy absorption assembly 100 between an engaged and disengaged state by selectively moving the at least one tooth of the pivotable member 106 into and out of engagement with the plurality of teeth 104 of the energy absorption belt 102. The pivotable member 106 is pivoted in response to movement of the manual adjustment lever 32.During axial and / or tilt adjustment of the steer-by-wire steering column assembly 10, the energy absorption assembly 100 is in the disengaged state, but when the manual adjustment assembly 30 is locked, the energy absorption assembly 100 is engaged and prepared for energy absorption.

[0020] The energy absorption assembly 100 includes a biasing member 108, such as a spring, connected to the adjustment pin 46 of the manual adjustment assembly 30. The biasing member 108 is also connected to the pivotable member 106 of the energy absorption assembly 100. The biasing member 108 biases the pivotable member 106 toward the engaged state so that its teeth engage the teeth 104 of the energy absorption belt 102. However, rotation of the adjustment pin 46 with the adjustment lever 32 overcomes the biasing force of the biasing member 108 to pivot the pivotable member 106 toward the disengaged state.

[0021] The embodiments disclosed herein provide a steer-by-wire steering column assembly 10 that has a simplified design in terms of component count and integrates the actuator and actuator housing with the steering column. This allows the entire system to axially translate together during adjustment in a compact package while still allowing for energy absorption capability.

[0022] Although the invention has been described in detail in connection with only a limited number of embodiments, it will be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention may be modified to incorporate any number of variations, alterations, substitutions, or equivalent arrangements not heretofore described, but which are within the spirit and scope of the invention. Furthermore, although various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Furthermore, any feature, element, component, or advantage of any embodiment may be utilized in any of the other embodiments. Accordingly, the invention is not to be considered limited by the foregoing description. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 525,067

[0001]

Claims

[1] Steer-by-wire steering column, comprising: a single column shell extending in a longitudinal direction; a single steering shaft extending in the longitudinal direction and at least partially housed within the single column shell; and an electric steer-by-wire actuator disposed at least partially within the single column shell and surrounding the single steering shaft to provide resistance to the single steering shaft. [2] The steer-by-wire steering column of claim 1, wherein the single column shell defines a first pair of slots for receiving an adjustment pin of a manual adjustment assembly therethrough. [3] The steer-by-wire steering column of claim 2, further comprising a housing end structure operatively coupled to an open end of the single column shell, the housing end structure defining a second pair of slots for receiving at least one component extending from a vehicle structure to which the single column shell and the housing end structure move relative. [4] The steer-by-wire steering column of claim 3, wherein a first position of the adjustment pin within the first pair of slots defines a fully axially inner position of the single column shell and the single steering shaft, and a second position of the adjustment pin within the first pair of slots defines a fully axially outer position of the single column shell and the single steering shaft. [5] The steer-by-wire steering column of claim 4, wherein the first position of the adjustment pin is located at a first end of the first pair of slots and the second position of the adjustment pin is spaced from a second end of the first pair of slots. [6] The steer-by-wire steering column of claim 3, wherein a first position of the at least one component within the second pair of slots defines a fully axially inner position of the single column shell and the single steering shaft, and a second position of the at least one component within the second pair of slots defines a fully axially outer position of the single column shell and the single steering shaft. [7] The steer-by-wire steering column of claim 6, wherein the first position of the at least one component is located at a first end of the second pair of slots and the second position of the at least one component is spaced from a second end of the second pair of slots. [8] The steer-by-wire steering column of claim 1, further comprising an energy absorption assembly, the energy absorption assembly comprising: an energy absorption belt coupled to an outer surface of the single column shell, the energy absorption belt having a plurality of teeth on a surface thereof; and a pivotable member having at least one tooth, the pivotable member being pivotable to selectively move the at least one tooth of the pivotable member into and out of engagement with the plurality of teeth of the energy absorption belt. [9] A steer-by-wire steering column according to claim 8, wherein the pivotable member of the energy absorption assembly is pivoted in response to movement of a manual adjustment lever. [10] The steer-by-wire steering column of claim 1, further comprising a rotational position sensor disposed within the single column shell for detecting an angular rotational position of the single steering shaft. [11] Steer-by-wire steering column according to claim 1, further comprising at least one travel stop limiter disposed within the single column shell to define a rotation limit for the single steering shaft in at least one rotational direction. [12] Steer-by-wire steering column according to claim 1, wherein the electric steer-by-wire actuator comprises: a rotor structure operatively coupled to a radially outer surface of the single steering shaft; and a motor stator that at least partially surrounds the rotor structure. [13] Steer-by-wire steering column, comprising: a single column shell extending in a longitudinal direction, the single column shell defining a first pair of slots for receiving an adjustment pin of a manual adjustment assembly therethrough, a first position of the adjustment pin within the first pair of slots defining a fully axially inner position of the single column shell and the single steering shaft, and a second position of the adjustment pin within the first pair of slots defining a fully axially outer position of the single column shell and the single steering shaft; a single steering shaft extending longitudinally and at least partially housed within the single column shell; an electric steer-by-wire actuator disposed at least partially within the single column shell and surrounding the single steering shaft to provide resistance to the single steering shaft, the electric steer-by-wire actuator comprising: a rotor structure operatively coupled to a radially outer surface of the single steering shaft; and a motor stator at least partially surrounding the rotor structure; and a housing end structure operatively coupled to an open end of the single column shroud, the housing end structure defining a second pair of slots for receiving at least one component extending from a vehicle structure to which the single column shroud and the housing end structure move relative, wherein a first position of the at least one component within the second pair of slots defines the fully axially inward position of the single column shroud and the single steering shaft, and a second position of the at least one component within the second pair of slots defines a fully axially outward position of the single column shroud and the single steering shaft. [14] The steer-by-wire steering column of claim 13, wherein the first position of the adjustment pin is located at a first end of the first pair of slots and the second position of the adjustment pin is spaced from a second end of the first pair of slots. [15] The steer-by-wire steering column of claim 13, wherein the first position of the at least one component is located at a first end of the second pair of slots and the second position of the at least one component is spaced from a second end of the second pair of slots. [16] Steer-by-wire steering column according to claim 13, further comprising an energy absorption assembly, the energy absorption assembly comprising: an energy absorption belt coupled to an outer surface of the single column shell, the energy absorption belt having a plurality of teeth on a surface thereof; and a pivotable member having at least one tooth, the pivotable member being pivotable to selectively move the at least one tooth of the pivotable member into and out of engagement with the plurality of teeth of the energy absorption belt. [17] A steer-by-wire steering column according to claim 16, wherein the pivotable member of the energy absorption assembly is pivoted in response to movement of a manual adjustment lever. [18] The steer-by-wire steering column of claim 13, further comprising a rotational position sensor disposed within the single column shell for detecting an angular rotational position of the single steering shaft. [19] Steer-by-wire steering column according to claim 13, further comprising at least one travel stop limiter arranged within the single column shell to define a rotation limit for the single steering shaft in at least one direction of rotation.

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