Steering column jacket reinforcement sleeve

Abstract

A steering column assembly includes a jacket having a first end, a second end, a jacket length, and an inner surface defining a hole. The steering column assembly also includes a steering shaft having an outer surface and a shaft length, at least a portion of the steering shaft being located within the hole defined by the inner surface of the jacket. The steering column assembly also includes a reinforcement sleeve having a radial inner surface, a radial outer surface, and a sleeve length, wherein the radial outer surface of the reinforcement sleeve is fixed to the inner surface of the jacket.

Description

Technical Field

[0001] The present disclosure relates to a vehicle steering system, and more particularly, to a reinforcement sleeve for a steering column jacket. Background Art

[0002] The steering column generally includes a jacket assembly, which may include an upper jacket and a lower jacket. The upper jacket is sensitive to both vertical and lateral natural frequencies. Increasing the material thickness of the entire upper jacket will result in an increase in the vertical and lateral natural frequencies, but such a change will also undesirably increase the mass of the upper jacket. Summary of the invention

[0003] According to one aspect of the present disclosure, a steering column assembly includes a jacket having a first end, a second end, a jacket length, and an inner surface defining a hole. The steering column assembly also includes a steering shaft having an outer surface and a shaft length, at least a portion of the steering shaft being located within the hole defined by the inner surface of the jacket. The steering column assembly also includes a reinforcement sleeve having a radial inner surface, a radial outer surface, and a sleeve length, wherein the radial outer surface of the reinforcement sleeve is fixed to the inner surface of the jacket.

[0004] According to another aspect of the present disclosure, a steering column assembly includes a jacket having an inner diameter, a first end, a second end, and an outer jacket length. The steering column assembly also includes an inner steering shaft having an outer diameter and a length. The steering column assembly also includes a bearing between the inner diameter of the outer jacket and the outer diameter of the inner steering shaft, the bearing being located at an end of the outer jacket, and the bearing radially supporting the inner steering shaft. The steering column assembly also includes a sleeve having an inner diameter, an outer diameter, a first end, a second end, and a sleeve length that is less than the length of the outer jacket. The steering column assembly also includes a sleeve positioned so that the outer diameter of the sleeve contacts the inner diameter of the outer jacket, and the end of the sleeve is not adjacent to the end of the outer jacket.

[0005] According to yet another aspect of the present disclosure, a method of securing a sleeve within another jacket of a steering column assembly is provided. The method includes providing an outer jacket having an inner diameter, a first end, a second end, and an outer jacket length. The method also includes providing an inner steering shaft having an outer diameter and a length. The method also includes providing a sleeve having an inner diameter, an outer diameter, and a sleeve length. The sleeve has a maximum outer diameter that is greater than the inner diameter of the outer jacket. The method also includes fully press-fitting the sleeve within the outer jacket such that the outer diameter of the sleeve is rigidly connected to the inner diameter of the outer jacket. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0007] Figure 1 is a perspective view of a steering column with a reinforced sleeve;

[0008] Figure 2 is a cross-sectional view of a steering column;

[0009] Figure 3 is a partial cross-sectional view of a steering column showing a reinforcement sleeve according to another aspect of the present disclosure.

[0010] Figure 4 is a perspective view of a reinforcement sleeve according to another aspect of the present disclosure; and

[0011] Figure 5 is a perspective view of a reinforcement sleeve according to another aspect of the present disclosure. DETAILED DESCRIPTION

[0012] Referring now to the accompanying drawings, in which the invention will be described with reference to a particular embodiment, without limiting the invention, there is shown a reinforcement sleeve for a steering column.

[0013] Reference Figure 1 and Figure 2 , a steering column is shown, and the steering column is generally marked with the reference numeral 10. The steering column 10 extends substantially along a longitudinal axis A. The steering column 10 is adjustable in a telescopic direction parallel to the longitudinal axis A (i.e., the steering column 10 is axially adjustable along the longitudinal axis A). More specifically, the steering column includes a steering shaft 12 rotatably disposed within a column assembly, the column assembly including an upper sleeve 14 and a lower sleeve 16. In some embodiments, the steering shaft 12 can be one of a plurality of operably coupled steering shafts. A steering wheel (not shown) is configured to be mounted to the steering shaft 12. The column sleeves 14, 16 and the steering shaft 12 extend substantially along the longitudinal axis A.

[0014] The upper jacket 14 extends from a first end 20 to a second end (not shown) to define a jacket length. An inner surface 22 of the upper jacket 14 defines a jacket hole 24. A portion of the length of the steering shaft 12 is positioned within the jacket hole 24, wherein the end of the steering shaft 12 protrudes from the first end 20 of the upper jacket 14 to attach a steering wheel.

[0015] The upper jacket 14 is subjected to various forces that cause vibrations, which cause the occurrence of vertical and lateral natural frequencies. The embodiments disclosed herein provide a reinforcing sleeve 30 to increase the stiffness of the upper jacket 14 and the entire steering column 10. The increased stiffness increases the natural frequency of the upper jacket 14 while minimizing the mass added to the steering column 10.

[0016] The reinforcing sleeve 30 is located between the outer surface 24 of the steering shaft 12 and the inner surface 22 of the upper jacket 14. The reinforcing sleeve 30 has a length positioned to the area of ​​the upper jacket 14 that is subjected to the most significant strain. Therefore, the reinforcing sleeve 30 has a length that is less than the jacket length of the upper jacket 14. This provides reinforcement of the upper jacket 14 while avoiding unnecessary thickening of the entire upper jacket 14 or a large portion thereof.

[0017] The reinforcement sleeve 30 includes a radially outer surface 32 and a radially inner surface 34. The reinforcement sleeve 30 can be formed of any suitable material. In some embodiments, the reinforcement sleeve 30 is formed of a metal structure. In other embodiments, the reinforcement sleeve 30 is laminated with a foam disposed between the radially inner surface 34 and the radially outer surface 32. The foregoing examples are merely illustrative of materials that can form the reinforcement sleeve 30 and are therefore not intended to be limiting.

[0018] The radial outer surface 32 is fixed to the inner surface 22 of the upper sleeve 14. The steering shaft 12 is radially supported in the sleeve bore 24 at least in part by a bearing 36, which is positioned in the sleeve bore 24, near the first end 20 of the upper sleeve 14. The steering shaft 12 can rotate therein in response to steering manipulation and input. The reinforcement sleeve 30 can be fixed in the sleeve bore 24 in various envisioned ways. In some embodiments, the reinforcement sleeve 30 is pressed into a ring defined by the outer surface 24 of the steering shaft 12 and the inner surface 22 of the upper sleeve 14. Such embodiments include an outer diameter of the reinforcement sleeve 30 that is greater than the inner diameter of the upper sleeve 14 in the unmounted state of the reinforcement sleeve 30 and the inner diameter of the reinforcement sleeve 30 is positioned to contact the outer surface 24 of the steering shaft 12. This size design allows the reinforcement sleeve 30 to be pressed into the ring. However, other methods of fixing the reinforcement sleeve 30 to the upper sleeve 14 and / or the steering shaft 12 can be envisioned.

[0019] Positioning the reinforcing sleeve 30 within the ring and in contact with the inner surface 22 of the outer jacket 14 provides a stiffer region of the upper jacket 14, thereby increasing the natural frequency response of the upper jacket.

[0020] The reinforcing sleeve 30 may be constructed in various forms. Figure 1 and Figure 2 In the embodiment of FIG. 1 , the reinforcing sleeve 30 extends continuously in the circumferential direction (i.e., 360 degrees). Figure 1 and Figure 2 In the illustrated embodiment, the radially outer surface 32 of the reinforcing sleeve 30 does not have a constant outer diameter. In other words, the radially outer surface 32 includes recesses, indentations, etc. Alternatively, the radially outer surface 32 may include protrusions. Any combination of recesses and protrusions may also be used. This may also be referred to as a "corrugated" outer surface.

[0021] Now refer to Figure 3, another variation of the radial outer surface 32 of the reinforcing sleeve 30 is shown. In the illustrated embodiment, the reinforcing sleeve 30 is cylindrical by continuously extending in the circumferential direction (i.e., 360 degrees). In addition, the radial outer surface 32 of the reinforcing sleeve 30 is smooth and has a constant cross-section. Specifically, the outer diameter of the reinforcing sleeve 30 is constant.

[0022] Reference Figure 4 and Figure 5 , shows other variations of the reinforcing sleeve 30. As shown, the reinforcing sleeve 30 does not extend continuously 360 degrees in the circumferential direction. Instead, the break 40 appears to allow the reinforcing sleeve 30 to bend during installation in the ring defined by the upper jacket 14 and the steering shaft 12. Figure 4 A radially outer surface 32 is shown having recesses and / or protrusions. Figure 5 A radially outer surface 32 is shown having a smooth and constant cross-section.

[0023] The embodiments disclosed herein provide a local reinforcement sleeve 30 to increase the natural frequency while avoiding a significant increase in the overall steering column jacket material thickness. This facilitates achieving both the natural frequency and quality targets required by the OEM.

[0024] 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. Rather, the present invention may be modified to include any number of variations, changes, substitutions, 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 embodiments described. Therefore, the present invention should not be considered to be limited by the foregoing description.

Claims

1. A steering column assembly, comprising: a sheath having a first end, a second end, a sheath length, and an inner surface that defines a bore; a steering shaft having an outer surface and a shaft length, at least a portion of the steering shaft being located within the bore defined by the inner surface of the sheath; and a reinforcing sleeve having a radially inner surface, a radially outer surface, and a sleeve length, wherein the radially outer surface of the reinforcing sleeve is fixed to the inner surface of the sheath, wherein the radially outer surface of the reinforcing sleeve is smooth and has a constant cross-section, and the outer diameter of the reinforcing sleeve is constant.

2. The steering column assembly according to claim 1, further comprising a bearing disposed between the sheath and the steering shaft, the bearing radially supporting the steering shaft, wherein, the bearing is positioned near the first end of the sheath.

3. The steering column assembly according to claim 1, wherein, in an uninstalled state of the reinforcing sleeve, the outer diameter of at least a portion of the radially outer surface of the reinforcing sleeve is greater than the inner diameter of at least a portion of the inner surface of the sheath.

4. The steering column assembly according to claim 1, wherein, the sleeve length is less than the sheath length.

5. The steering column assembly according to claim 1, wherein, the reinforcing sleeve is non-cylindrical.

6. The steering column assembly according to claim 5, wherein, the cross-section of the reinforcing sleeve is non-uniform along the sleeve length.

7. The steering column assembly according to claim 1, wherein, the reinforcing sleeve is metallic.

8. The steering column assembly according to claim 1, wherein, the radially outer surface of the reinforcing sleeve includes a corrugated portion.

9. The steering column assembly according to claim 1, wherein, the reinforcing sleeve is laminated with foam disposed between the radially inner surface and the radially outer surface.

10. The steering column assembly according to claim 1, wherein, the radially outer surface of the reinforcing sleeve includes a plurality of recesses.

11. A steering column assembly, comprising: a sheath having an inner diameter, a first end, a second end, and an outer sheath length; an inner steering shaft having an outer diameter and a length; a bearing disposed between the inner diameter of the outer sheath and the outer diameter of the inner steering shaft, the bearing being located at an end of the outer sheath, and the bearing radially supporting the inner steering shaft; a sleeve having an inner diameter, an outer diameter, a first end, a second end, and a sleeve length less than the outer sheath length; and the sleeve is positioned such that the outer diameter of the sleeve contacts the inner diameter of the outer sheath, and the ends of the sleeve are not adjacent to the ends of the outer sheath, wherein the radially outer surface of the sleeve is smooth and has a constant cross-section, and the outer diameter of the sleeve is constant.

12. The steering column assembly according to claim 11, wherein, the outer diameter of the sleeve is greater than the inner diameter of the outer sheath.

13. The steering column assembly according to claim 11, wherein, the sleeve is non-cylindrical.

14. The steering column assembly according to claim 13, wherein, The cross-section of the sleeve is non-uniform over the length of the sleeve.

15. The steering column assembly according to claim 11, in, The sleeve is non-cylindrical.

16. The steering column assembly according to claim 15, in, The cross-section of the sleeve is non-uniform over the length of the sleeve.

17. The steering column assembly according to claim 11, in, The sleeve has a metal structure.

18. A method of securing a sleeve within another jacket of a steering column assembly, include: providing an outer sheath having an inner diameter, a first end, a second end, and an outer sheath length; providing an inner steering shaft having an outer diameter and a length; providing a sleeve having an inner diameter, an outer diameter, and a sleeve length, wherein the maximum outer diameter of the sleeve is greater than the inner diameter of the outer sheath; and fully press-fitting the sleeve into the outer sheath such that the outer diameter of the sleeve is rigidly connected to the inner diameter of the outer sheath, Wherein, the radial outer surface of the sleeve is smooth and has a constant cross section, and the outer diameter of the sleeve is constant.

19. The method according to claim 18, in, During the process of press-fitting the sleeve into the outer jacket, the sleeve is compressed circumferentially.

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