Steering column mounting bracket release feature

Abstract

A steering column assembly has a mounting bracket configured for attachment to a fixed vehicle support member in a releasably fixed position and for release from the fixed vehicle support member to a released position during a steering column energy absorption event. A steering jacket is operably supported by the mounting bracket. The steering jacket has at least one interface feature arranged to face the mounting bracket during the steering column energy absorption event to inhibit rotational movement of the mounting bracket relative to the steering jacket when the mounting bracket moves from the fixed position to the released position.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 545,512, filed on October 24, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to steering column assemblies, and more particularly, to steering column assemblies having releasable mounting brackets. Background Art

[0004] A known automotive steering column assembly includes a mounting bracket releasably attached to a vehicle frame member for intentional release during a driver-steering wheel collision. It is desirable that the mounting bracket releases smoothly from the frame member without binding between the mounting bracket and the vehicle frame member. Unfortunately, the mounting bracket may tilt relative to the vehicle frame member during release, thereby causing undesirable resistance and binding between the mounting bracket and the vehicle frame member. Summary of the invention

[0005] According to one aspect of the present disclosure, a steering column assembly includes a mounting bracket configured for attachment to a fixed vehicle support member in a releasably fixed position and for release from the fixed vehicle support member to a released position during a steering column energy absorbing event. A steering jacket is operably supported by the mounting bracket. The steering jacket has at least one interface feature arranged to confront the mounting bracket during the steering column energy absorbing event to inhibit rotational movement of the mounting bracket relative to the steering jacket when the mounting bracket moves from the fixed position to the released position.

[0006] According to one aspect of the present disclosure, a method for causing a steering jacket to inhibit rotation of a mounting plate when the mounting plate moves from a position where it is releasably secured to a fixed vehicle support member to a position where it is released from the fixed vehicle support member during a steering column energy absorbing event includes providing a steering jacket having at least one interface feature extending toward the mounting plate, the at least one interface feature being arranged to face the mounting plate during the steering column energy absorbing event so as to inhibit rotational movement of the mounting plate relative to the steering jacket when the mounting plate moves from the releasably secured position to the released position.

[0007] These and other advantages and features will become more apparent from the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of this specification. The foregoing and other features and advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0009] Figure 1 is a perspective view of a motor vehicle including a steering column assembly constructed according to one aspect of the present disclosure;

[0010] Figure 2 yes Figure 1 A partial side view of a steering column assembly;

[0011] Figure 2A yes Figure 2 A perspective view of a steering column assembly;

[0012] Figure 2B is a fragmentary view looking generally along a longitudinal axis of the steering column assembly toward a mounting bracket of the steering column assembly, the mounting bracket being shown spaced apart by a gap from an interface feature of a steering column jacket of the steering column assembly prior to an energy absorbing event;

[0013] Figure 2C is similar to Figure 2B , showing a steering column assembly during an energy absorbing event according to the present disclosure, wherein the interface feature inhibits rotation of the mounting bracket;

[0014] Figure 3 is similar to Figure 2A with various components removed for clarity to illustrate interface features on a steering column cover constructed in accordance with one aspect of the present disclosure; and

[0015] Figure 4 is similar to Figure 3 , showing interface features on a steering column cover constructed according to another aspect of the present disclosure. DETAILED DESCRIPTION

[0016] Referring now to the accompanying drawings, the present disclosure will be described with reference to specific embodiments relating to steering shaft assemblies and clamping yokes. It should be understood that the disclosed embodiments are merely illustrative of the present disclosure and can be embodied in various and alternative forms. Various elements of the disclosed embodiments may be combined or omitted to form other embodiments of the present disclosure. The drawings are not necessarily drawn to scale; some features may be enlarged or reduced to show details of particular components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art to use the present disclosure in various ways.

[0017] Figure 1A motor vehicle 10 having a steering column assembly 12 constructed in accordance with one aspect of the present disclosure is shown operatively coupled to a steering gear assembly 14 via a steering shaft assembly, such as an intermediate shaft assembly, hereinafter referred to as intermediate shaft 16. The steering column assembly 12 has a steering jacket assembly including one or more coaxially aligned steering jackets, wherein an upper steering jacket 18 is shown supported by a mounting bracket 20. The mounting bracket 20 is configured for attachment to a fixed vehicle support member 22, such as a vehicle frame member, by way of example and not limitation, in a releasably fixed position, such as via an energy absorbing strap 23. The mounting bracket 20 is configured to be released from the fixed vehicle support member 22, whereupon the mounting bracket 20 translates in sliding relationship with the upper steering jacket 18 along the energy absorbing strip 23, and according to the present disclosure, the mounting bracket 20 translates to a released position without rotation, or at least substantially without rotation (meaning that the mounting bracket rotates only about 0.1 degrees to 5 degrees, more preferably less than 3 degrees, if the mounting bracket rotates) relative to the upper steering jacket 18 during a steering column energy absorbing event. The minimal relative rotation between the upper steering jacket 18 and the mounting bracket 20 facilitates smooth sliding translation of the mounting bracket 20 and the upper steering jacket 18 relative to the energy absorbing strip 23 without binding the mounting bracket 20, thereby absorbing energy and minimizing potential injury to the driver. Energy absorption may even occur during a crash condition whereby a driver of the motor vehicle 10 may strike the steering wheel 24 of the steering column assembly 12 , thereby causing an impact force F acting generally along the longitudinal axis 26 of the steering column assembly 12 to cause the upper steering jacket 18 to move axially generally along the longitudinal axis 26 toward the front end 28 of the motor vehicle 10 .

[0018] The mounting bracket 20 of the steering column assembly 10 is a rake type mounting bracket in which actuation of a lever 30 (operating lever) supported by a bolt 32 releases the steering column assembly 12 for tilting movement desired by the driver. When the steering column assembly 12 is oriented in the desired tilt orientation, the driver locks the steering column assembly 12 in place via the lever 30. The mounting bracket 20 includes a pair of release capsule slots, hereinafter referred to as release slots 31.

[0019] During a steering column energy absorbing event, such as when the front end 28 of the motor vehicle 10 is subjected to an impact force (this is by way of example and not limitation), a force F is transmitted from the compression bracket 34 secured to the upper steering jacket 18 to the mounting bracket 20 via the bolt 32. The release slot 31 of the mounting bracket 20 is then caused to disengage from the vehicle support member 22, whereupon the mounting bracket 20 slides smoothly along the energy absorbing strip 23 without tilting (also referred to as rotating).

[0020] As the mounting bracket 20 separates from the vehicle support member 22 and begins to slide along the energy absorbing strip 23, smooth, generally planar motion is facilitated, which motion is intended to mean that the upper planar surface 20a of the mounting bracket 20 translates along the plane P and has no tilt or no significant tilt (minimal tilt, such as less than 3 degrees) relative to the plane P. The plane P is defined as being parallel or substantially parallel (intended to mean within 5 degrees or less of true parallel) to the upper planar surface 20a of the mounting bracket 20 and parallel or substantially parallel (intended to mean within 5 degrees or less of true parallel) to the longitudinal axis A. Thus, smooth, unrestrained motion of the mounting plate 20 along the energy absorbing strip 23 is facilitated via at least one stabilizing feature (also referred to as an interface feature 36) that is arranged to face the mounting bracket 20 during a steering column energy absorbing event to inhibit rotational motion of the mounting bracket 20 relative to the steering jacket 18 as the mounting bracket 20 moves from a secured position to a released position. In this way, the reaction load (binding friction) between the mounting bracket 20 and the release slot 31 is minimized, and therefore, the mounting bracket 20 is freely released from the release slot 31 under an energy absorption event, thereby preventing the mounting bracket 20 from deforming and the movement of the mounting bracket 20 is controlled by the energy absorption strip 23 as expected, thereby controlling the energy load distribution. Figure 3 As best shown in the non-limiting embodiment of the embodiment of the present invention, the interface features 36 are provided as a plurality of interface features 36 secured to the upper steering jacket 18. The interface features 36 are formed as an integral piece of material of the upper steering jacket 18 and may be formed as a plastically deformed material of the upper steering jacket 18, such as in a mechanical material upsetting operation (including stamping), by way of example and not limitation. Thus, no additional material is required to form the interface features 36 in addition to the material of the upper steering jacket 18.

[0021] The interface feature 36 extends radially outward from the outer surface of the upper steering boot 18. In the non-limiting embodiment shown, the interface feature 36 extends radially outward from the outer surface 38 (such as the generally straight cylindrical outer surface 38 of the upper steering boot 18, by way of example and not limitation) toward the mounting bracket 20, which is generally intended to mean that the outer surface 38 can be purely straight and purely cylindrical, or slightly less straight (such as differing from purely straight by up to about 3 degrees) and slightly deviating from a cylindrical profile (such as being non-cylindrical in visual appearance). Thus, the interface feature 36 reduces the gap G ( Figure 2B, viewed generally along the longitudinal axis 26 from the steering wheel 24 toward the mounting bracket 20), the gap extends between the upper steering jacket 18 and the mounting bracket 20, and specifically extends between the apex of the interface feature 36 and the bottom surface of the mounting bracket 20. The interface features 36 are shown as being circumferentially spaced apart from each other and equally spaced apart from the end 40 of the upper steering jacket 18. Thus, when the upper steering jacket 18 moves generally along the longitudinal axis 26 in an energy absorbing event (e.g., Figure 2 1 and 12. The interface feature 36 faces and engages a rearwardly facing surface 43 of the mounting bracket 20 (such as extending upwardly from a bottom surface 42 of the mounting bracket 20), thereby causing the mounting bracket 20 and the upper steering boot to engage with each other and move simultaneously. The bottom surface 42 is shown as having a radiused scalloped area (hereinafter referred to as the scalloped portion 44) that is contoured to provide clearance for the upper steering boot 18 to the mounting bracket 20 in a rake up (uppermost adjustment of the steering column assembly 12 during normal use) position of the steering column assembly 12. The interface feature 36 is arranged and aligned to provide clearance for the upper steering boot 18 to the mounting bracket 20 during an energy absorption event ( Figure 2C ) faces and abuts surface 43 of an area adjacent to the arcuate scallop 44, thereby causing the mounting bracket 20 to translate along the plane P with the upper steering boot 18. Thus, the extent to which the interface feature 36 needs to extend outwardly from the outer surface 38 of the upper steering boot 18 to engage the surface 43 is minimized, such as between about 1 mm and 5 mm, more preferably between about 1 mm and 3 mm.

[0022] Because the interface feature engages the surface 43 of the mounting bracket 20 during the energy absorption event, the force transmitted to the mounting bracket 20 via the bolt 32 is counteracted by the force F1 exerted on the surface 43 by the interface feature 42, thereby inhibiting the mounting bracket 20 from rotating downward relative to the upper steering jacket 18 and the vehicle support member 22. It is contemplated that the mounting bracket 20 may undergo a very small degree of rotational movement, such as between about 1-5 degrees at most, preferably less than 3 degrees. Therefore, the movement of the mounting bracket 20 during the energy absorption event can be a pure translation without rotation, or a substantially translational movement with the upper steering jacket 18 without a high degree of rotation, as discussed above.

[0023] like Figure 4As another non-limiting embodiment of the present disclosure, the steering column assembly 112 is shown having an interface feature 136 constructed in accordance with another aspect of the present disclosure. The interface feature 136 functions as discussed above with respect to the interface feature 36, but rather than being formed as a plurality of interface features spaced apart from one another, the interface feature 136 is formed as a single interface feature. The interface feature 136 is shown extending along a circumferential direction of the cylindrical outer surface 38 of the upper steering jacket 18 over a majority of the length or the entire length of the scallop 44, thereby providing maximum resistance to rotation of the mounting bracket 20 when forcefully impacting the surface 43 during an energy absorbing event.

[0024] According to another aspect of the present disclosure, a method is provided for causing a steering jacket 18 to inhibit rotation of a mounting bracket (also referred to as a mounting plate 20) when the mounting plate 20 moves from a position releasably secured to a fixed vehicle support member 22 to a position released from the fixed vehicle support member 22 during a steering column energy absorbing event. The method includes providing the steering jacket 18 having at least one interface feature 36 extending toward the mounting plate 20, the at least one interface feature 36 being arranged to face the mounting plate 20 during a steering column energy absorbing event so as to inhibit rotational movement of the mounting plate 20 relative to the steering jacket 18 when the mounting plate 20 moves from a releasably secured position to a released position.

[0025] The method may also include providing the at least one interface feature 36 as an integral piece of material with the steering jacket 18 .

[0026] The method may further include providing the at least one interface feature as a plurality of interface features 36, and further, providing the plurality of interface features 36 to be circumferentially spaced apart from one another around an outer surface 38 of the steering jacket 18. Furthermore, the method may include providing the plurality of interface features 36 to be in an equidistantly spaced relationship from an end 40 of the steering jacket 18.

[0027] The method may further include providing the at least one interface feature as a single interface feature 36 , and further providing the single interface feature 36 as the plastically deformed material of the steering jacket 18 , wherein the interface feature 36 extends radially outward from a generally cylindrical outer surface 38 of the steering jacket 18 .

[0028] Although the present invention has been described in detail in conjunction with only a limited number of embodiments, it should be readily understood that the present invention is not limited to these disclosed embodiments. On the contrary, the present invention may be modified to include any number of changes, modifications, permutations, or equivalent arrangements not previously described but commensurate with the spirit and scope of the present invention. In addition, although various embodiments of the present invention have been described, it should be understood that aspects of the present invention may include only some of the described embodiments. Therefore, the present invention should not be considered to be limited by the foregoing description.

Claims

1. A steering column assembly, comprising: a mounting bracket configured for attachment to a fixed vehicle support member in a releasably secured position and for release from the fixed vehicle support member to a released position during a steering column energy absorbing event; as well as a steering boot operably supported by the mounting bracket, the steering boot having at least one interface feature disposed to face the mounting bracket during the steering column energy absorbing event to inhibit rotational movement of the mounting bracket relative to the steering boot when the mounting bracket moves from the releasably secured position to the released position.

2. The steering column assembly of claim 1, wherein the at least one interface feature is an integral piece of material of the steering boot.

3. The steering column assembly of claim 2, wherein the at least one interface feature is a plastically deformable material of the steering boot.

4. The steering column assembly of claim 1, wherein the at least one interface feature extends radially outward from the generally cylindrical outer surface of the steering boot toward the mounting bracket.

5. The steering column assembly of claim 1, wherein the at least one interface feature comprises a plurality of interface features.

6. The steering column assembly of claim 5, wherein the plurality of interface features are circumferentially spaced from one another. 7 . The steering column assembly of claim 6 , wherein the plurality of interface features are equally spaced from an end of the steering boot.

8. The steering column assembly of claim 1, wherein the at least one interface feature is a single interface feature.

9. The steering column assembly of claim 8, wherein the interface feature extends radially outward from the generally cylindrical outer surface of the steering boot toward the mounting bracket.

10. The steering column assembly of claim 9, wherein the interface feature extends in a circumferential direction around a portion of the generally cylindrical outer surface.

11. The steering column assembly of claim 1 , wherein the at least one interface feature is configured to engage a peripheral edge of the mounting bracket.

12. The steering column assembly of claim 1, wherein the mounting bracket is a rake-type bracket.

13. A method of causing a steering boot to inhibit rotation of a mounting plate when the mounting plate moves from a position releasably secured to a fixed vehicle support member to a position released from the fixed vehicle support member during a steering column energy absorbing event, the method comprising: The steering jacket is provided having at least one interface feature extending toward the mounting plate, the at least one interface feature being arranged to face the mounting plate during the steering column energy absorbing event so as to inhibit rotational movement of the mounting plate relative to the steering jacket when the mounting plate moves from the releasably secured position to the released position.

14. The method of claim 13, further comprising providing the at least one interface feature as an integral piece of material with the steering boot.

15. The method of claim 13, further comprising configuring the at least one interface feature as a plurality of interface features.

16. The method of claim 15, further comprising disposing the plurality of interface features in circumferentially spaced relationship from one another about an outer surface of the turning sleeve.

17. The method of claim 16, further comprising disposing the plurality of interface features in an equidistantly spaced relationship from an end of the steering boot.

18. The method of claim 15, further comprising providing the plurality of interface features by plastically deformed material of the steering jacket, wherein the plurality of interface features extend radially outward from a generally cylindrical outer surface of the steering jacket.

19. The method of claim 13, further comprising setting the at least one interface feature as a single interface feature.

20. The method of claim 19, further comprising providing the interface feature as a plastically deformable material of the steering boot, wherein the interface feature extends radially outward from a generally cylindrical outer surface of the steering boot.

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