Energy absorbing assembly for adjustable steering columns

Abstract

An axially adjustable steering column includes a first jacket and a second jacket axially movable relative to the first jacket. The second jacket includes a window, and the first jacket includes a connector opening. An energy absorbing assembly includes a locking cam positioned within the window and connected to the second jacket; and a strap body connected to the first jacket by a fastener extending through the strap body and the connector opening. The connector opening includes a ramp for ejecting the fastener from engagement with the first jacket.

Description

Technical Field

[0001] The following description relates to energy absorbing devices, and more particularly to energy absorbing straps and locking cams in adjustable steering columns. Background Art

[0002] Vehicles (such as cars, trucks, sport utility vehicles, crossovers, minivans, boats, aircraft, all-terrain vehicles, recreational vehicles, or other suitable vehicles) include various steering system solutions, for example, steer-by-wire and driver interface steering. These steering system solutions typically include a steering column assembly to convert steering inputs into outputs that interact with a steering linkage to ultimately steer the wheels. Regardless of the steering solution, the steering column assembly includes various safety features, such as air bags for reducing impact forces. In addition, many steering column assemblies are collapsible and include one or more energy absorbing features, such as energy absorbing straps, that allow a certain amount of controlled compression.

[0003] Some energy-absorbing straps are configured to coil along their length to absorb energy and are often referred to as coiled straps. Typically, during an impact, coiled straps absorb energy as the strap deforms, where the kinetic energy can be dissipated through compression of the steering column assembly. Key considerations when designing energy-absorbing straps include load requirements, compatibility, and packaging. The performance of an energy-absorbing strap during a collapse event is traditionally influenced by many factors, including material thickness / width, material properties, and / or strap shape or characteristics. Therefore, the performance of an energy-absorbing strap can be modified on a vehicle-by-vehicle basis by modifying these properties, but packaging requirements often limit the changes that can be made, and meeting specific requirements at specific stages of the collapse cycle can be quite complex. For example, the lower jacket often also requires a large gap to allow the strap to travel, which requires additional material to compensate for the loss of stiffness and strength. It is often necessary to leave space for the tail of the strap to be delivered unimpeded, thereby controlling the absorbed load, further complicating packaging.

[0004] Therefore, there remains a need for an operational framework that improves energy absorption characteristics to address packaging, load requirements, and scalability. Summary of the Invention

[0005] One aspect of the present disclosure includes an axially adjustable steering column. The steering column includes a first jacket and a second jacket that is axially movable relative to the first jacket. The first jacket includes at least one connector opening. An energy absorbing assembly includes a strap body connected to the first jacket via at least one fastener extending through the strap body and the at least one connector opening.

[0006] Another aspect of the present disclosure includes an energy absorbing assembly for an axially adjustable steering column. The energy absorbing assembly includes a strap body extending between a first end and a second end, the first end being configured to be positioned exteriorly of a first sheath and the second end being configured to be positioned interiorly of the first sheath. A curved portion is positioned between the first end and the second end. A first segment extends between the curved portion and the first end, and a second segment extends between the curved portion and the second end. The first segment includes at least one upper aperture for receiving a fastener to connect the first segment to the exterior of the first sheath.

[0007] The features and technical advantages of the present invention have been summarized in a rather broad manner so that the specific embodiments of the present invention that follow can be better understood. Additional features and advantages of the present invention will be described below, which form the subject matter of the present invention for which protection is sought. It will be understood by those skilled in the art that the disclosed concepts and specific embodiments can be easily used as a basis for modifying or designing other embodiments to achieve the same purposes of the present invention. It will also be appreciated by those skilled in the art that such equivalent embodiments do not depart from the spirit and scope of the present invention as set forth in the appended claims. This section provides a general overview of the present disclosure, which should not be construed as a complete and comprehensive enumeration of all objects, aspects, features and advantages associated with the present disclosure. These and other aspects of the present disclosure are disclosed in the detailed description of the following specific embodiments, the appended claims, and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present disclosure will be best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not drawn to scale unless otherwise indicated herein. Instead, the dimensions of the various features are arbitrarily expanded or reduced for clarity.

[0009] Figure 1 A vehicle with a steering system according to the principles of the present disclosure is generally shown.

[0010] Figure 2 A steering column is generally shown with an energy absorbing assembly for dissipating kinetic energy between a first jacket and a second jacket.

[0011] Figure 3 Overall, it shows Figure 2 Exploded view of a steering column with a strip body according to a first arrangement.

[0012] Figure 4 An enlarged side view of an energy absorbing device having a strap body according to a first arrangement is generally shown.

[0013] Figure 5 A side view of an energy absorbing device having a strap body according to a second arrangement is generally shown. DETAILED DESCRIPTION

[0014] The following discussion is directed to various embodiments of the present disclosure. Although one or more of these embodiments may be described in greater detail than other embodiments, the disclosed embodiments should not be interpreted or otherwise used to limit the scope of the present disclosure, including the claims. Furthermore, those skilled in the art will appreciate that the following description has broad applicability, and that the discussion of any embodiment is merely intended to illustrate that embodiment and is not intended to limit the scope of the present disclosure, including the claims, to that embodiment.

[0015] As described above, vehicles (such as automobiles, trucks, sport utility vehicles, crossovers, minivans, boats, airplanes, all-terrain vehicles, recreational vehicles, or other suitable vehicles) include various steering system solutions, such as steer-by-wire and driver interface steering. These steering system solutions typically include a steering column assembly for converting steering inputs into outputs that interact with a steering linkage to ultimately steer the wheels of the vehicle. Regardless of the steering solution, the steering column assembly includes various safety features, such as air bags for reducing impact forces. In addition, many steering column assemblies are collapsible and include one or more energy absorbing features, such as energy absorbing straps, that allow for a certain amount of compression.

[0016] First refer to Figure 1 , a vehicle 20 is generally shown according to the principles of the present disclosure. The vehicle 20 may include any suitable vehicle, such as a car, truck, sport utility vehicle, minivan, crossover, any other passenger vehicle, any suitable commercial vehicle, or any other suitable vehicle. Although the vehicle 20 may be a passenger vehicle having wheels and used on roads, the principles of the present disclosure may be applied to other vehicles, such as airplanes, tractors, boats, or other suitable vehicles. The vehicle 20 may include a propulsion system 30, such as an ignition system, an electronic system, or a combination thereof.

[0017] In some embodiments, the vehicle 20 may further include a steering system 40. The steering system 40 may be configured as a driver interface steering system, an autonomous driving system, or a system that allows driver interface and autonomous steering. The steering system may include an input device 42, such as a steering wheel, wherein the driver can mechanically provide steering input by turning the steering wheel. The steering column assembly 44 may include a steering column 45, which extends along an axis from the input device 42 to an output assembly 46. The output assembly 46 may include a pinion shaft assembly, an I-shaft, a universal joint, a steer-by-wire component, or any other feature that is traditionally located opposite the input device 42.

[0018] The steering column 45 may include at least two axially adjustable portions, for example, a first sleeve 48 and a second sleeve 50 that are axially adjustable relative to each other. The first sleeve 48 may be an upper sleeve and the second sleeve 50 may be a lower sleeve, wherein the first sleeve 48 and the second sleeve 50 are permitted to move axially relative to each other during an impact or other compressive force. The axial movement may include sliding, telescoping, translating, and other axial motions. The steering column assembly 44 may include additional portions that permit axial motion and brackets that provide rake and tilt motions. More specifically, the steering column assembly 44 may include a powered actuator (not shown) wherein the axial adjustment is machine driven.

[0019] The energy absorbing assembly 52 may be located on one or each of the first jacket 48 , the second jacket 50 , any bracket, or a combination thereof and may provide at least one of a variable travel load absorbing arrangement and a steering column locking function. The energy absorbing assembly may dissipate kinetic energy between the first jacket 48 and the second jacket 50 .

[0020] The steering gear assembly 54 can be connected to the output assembly 46 via a steering gear input shaft 56. The steering gear assembly 54 can be configured as a rack and pinion, a recirculating ball steering gear, or any other type of steering gear associated with an autonomous driver interface steering system. The steering gear assembly 54 can then be connected to a drive shaft 58 via an output shaft 60. The output shaft 60 can include a steering rocker arm and a sector gear or other conventional components. The output shaft 60 is operatively connected to the steering gear assembly 54 such that rotation of the steering gear input shaft 56 causes corresponding movement of the output shaft 60 and causes the drive shaft to steer the wheels 61.

[0021] Figure 2 A steering column 45 is generally shown with an energy absorbing assembly 52 for dissipating kinetic energy between a first jacket 48 and a second jacket 50. The first jacket 48 and the second jacket 50 extend along an axis A. The energy absorbing assembly 52 can be connected to the first jacket 48 (upper jacket), the second jacket 50 (lower jacket), or a combination thereof. In some embodiments, the energy absorbing assembly 52 includes an energy absorbing roll-up strap body 64 that is at least partially coupled to the first jacket 48 and extends at least partially between the first jacket 48 and the second jacket 50. During a collapse event, a force "Fx" can cause the first jacket 48 to move or collapse into the second jacket 50 along the axis A, and the energy absorbing assembly 52 dissipates at least some of the kinetic energy of the collapsing first jacket 48 and the second jacket 50.

[0022] Continue to refer to Figure 2, the energy absorbing assembly 52 may also include an energy absorbing actuator 66. The energy absorbing actuator 66 includes a locking cam 68 that moves between a locked position and an unlocked position. In the locked position, the locking cam 68 is hinged to be in locking engagement with the strip body 64. In the unlocked position, the locking cam 68 is hinged so that it is separated from the strip body 64. In some embodiments, the second sheath 50 includes a window 70 for positioning at least a portion of the locking cam 68. The locking cam 68 includes a toothed portion 72, a tail portion 74, and a body 76 that separates the toothed portion 72 from the tail portion 74. The body 76 defines an opening 78 for accommodating a pivot pin 80. In some embodiments, the second sheath 50 includes a hole 82 for inserting the pivot pin 80 and pivotally connecting the locking cam 68 to the second sheath 50. The window 70 may also include a clamping groove 84 that is transverse to the axis A for clamping the first sheath 48 and the window 70.

[0023] Now refer to Figure 3 and Figure 4 , shows an energy absorbing rolled-up strap body 64A according to a first arrangement. The strap body 64A may include a first end 86A and a second end 88A separated from the first end 86A by an intermediate portion 90A. The first end 86A may be located on the outer surface of the first jacket 48, and the second end 88A may be located on the inner surface of the outer jacket 48 ( Figure 4 ). The middle portion 90A includes a curved portion 92A. When the first end 86A remains stationary and the second end 88A moves in the direction of the force "Fx" ( Figure 2 ), the curved portion 92A can help the strip body 64A "roll up" during a collapse event. The middle portion 90A can include an initial collapse or roll-up area 94A located between the first segment 96A and the second segment 98A. The first segment 96A can extend from the first end 86A to the middle portion 90A. The initial roll-up area 94A represents a location where roll-up or deformation begins, at which position the "rolling up" or deformation of the strip body 64A begins during a collapse event. The second segment 98A can extend between the middle portion 90A and the second end 88A.

[0024] The first section 96A includes a series of teeth 100A extending therefrom. A pair of side walls 102A can extend along the first section 96A on opposite sides of the teeth 100A. Each side wall 102A can extend between a lower stop tab 104A and an upper stop tab 106A. In use, the lower stop tab 104A can contact a portion of the energy-absorbing actuator 66 (e.g., the pivot pin 80) and create a hard stop in a first direction, and the upper stop tab 106A can contact a portion of the energy-absorbing actuator 66 and create a hard stop in a second direction.

[0025] Continue to refer to Figure 3 and Figure 4 , the first section 96A may include at least one upper hole 108A (e.g., a pair of upper holes 108A). The pair of upper holes 108A may be separated by teeth 100A. In some embodiments, the second section 98A may include at least one lower hole 110A aligned with at least one of the upper holes 108A. The connector 112 may be positioned through each upper hole 108A. In some embodiments, the connector 112 may include a rivet, and during assembly, the rivet may be driven through at least one of the upper holes 108A and at least one of the lower holes 110A before the rivet tail (not shown) is deformed between the at least one upper hole 108A and the at least one lower hole 110A. The locking cam 68 moves between a locked position and an unlocked position. In the locked position ( Figure 4 ), the locking cam 68 is hinged to lockably engage with the teeth 100A on the strip body 64A. In the unlocked position, the locking cam 68 is hinged so that it is spaced apart from the teeth 100A on the strip body 64A.

[0026] The first sheath 48 can include at least one connector opening 114 (e.g., a pair of connector openings 114). Each connector opening 114 can include a spray hole 116 and a retaining slot 118. The retaining slot 118 can be positioned on the first sheath 48 and extend toward the second sheath 50, and the spray hole 116 can be consistent with and extend from the retaining slot 118 (e.g., toward the end of the first sheath 48 opposite the second sheath 50). During assembly, the connector 112 can be placed through the strip body 64A in each connector opening 114 (e.g., the retaining slot 118). As shown in Figure 4 As best shown in FIG, connector 112 includes a lower head 120 and an upper head 122 separated from lower head 120 by a connector body 124 that provides a smaller cross-section than lower head 120 and upper head 122. Thus, when connector body 124 is inserted into retaining slot 118A, it is locked against radial and circumferential movement relative to axis A and further locked against axial movement along axis A toward second sheath 50.

[0027] The first sheath 48 may also include a ramp 126 extending into each injection hole 116. Each ramp 126 may be integral with the sheath 48 (eg, stamped or otherwise deformed) and include a half-bowl shape ( Figure 3). In other arrangements, each ramp 126 can be planar or otherwise shaped. During use, when the first sheath 48 is compressed relative to the second sheath 50 along the axis A, the ramp 126 can guide the lower head 120 out of the connector opening 114. In some embodiments, the first segment 96A can extend a first distance from the middle portion 90A along the axis A, and the second segment 98A can extend a second distance less than the first distance from the middle portion 90A. In some embodiments, the second end 88A terminates before the upper aperture 108A. In some embodiments, the second end 88A can extend an equal distance from the first end 86A and have a second lower aperture (not shown).

[0028] The first sheath 48 may also include a distal end that engages the curved portion 92. More specifically, the distal end may be oriented toward the second sheath 50 and define a recess 128 sized to receive the curved portion 92. Figure 4 As best shown in FIG, the second segment 98A of the strap body 64A can define an arcuate portion extending toward the first segment 96A. The arcuate portion 130A can be at least partially positioned between the first and second ramps 126 spaced apart along the axis A.

[0029] Now refer to Figure 5 , shows a strip body 64B according to a second arrangement. The strip body 64B may include all the same features, structures and materials as described in the first arrangement. However, the strip body 64B may include a changed connection to the first sheath 48. More specifically, the strip body 64B may include a single upper hole 108B. The upper hole 108B may be located near the first end 64B. A connector 112 (e.g., a rivet) may extend through the upper hole 108B into the connector opening 114, as described above. In some embodiments, the first segment 96B may extend a first distance from the middle portion 90B along the axis A, and the second segment 98B may extend a second distance from the middle portion 90B that is less than the first distance. In some embodiments, the second end 88B may terminate before the upper hole 108B.

[0030] Although the present invention has been described in detail with reference to only a limited number of embodiments, it will 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, alterations, substitutions, or equivalent arrangements not heretofore described but commensurate with the concept and scope of the present invention. Additionally, although various embodiments of the present invention have been described, it will be understood that aspects of the present invention may include only some of the described embodiments. Furthermore, any features, elements, components, or advantages of any one embodiment may be used in any other embodiment. Therefore, the present invention should not be construed as being limited by the foregoing description.

Claims

1. An axially adjustable steering column, comprising: a first sheath and a second sheath, wherein the second sheath is axially movable relative to the first sheath; The first sheath includes at least one connector opening; an energy absorbing assembly comprising a strap body connected to the first jacket by at least one fastener extending through the strap body and the at least one connector opening, Wherein, the at least one connector opening includes an injection hole and a retaining groove.

2. The steering column according to claim 1, wherein: The fastener includes an upper head, a lower head and a body.

3. The steering column according to claim 2, wherein: The retaining slot is sized to prevent the lower head from passing therethrough.

4. The steering column according to claim 3, wherein: The body is located in the retaining groove.

5. The steering column according to claim 4, wherein: The first jacket extends from an upper end of the steering column, and the second jacket extends from a lower end of the steering column.

6. The steering column according to claim 5, wherein: The retaining groove is oriented toward the lower end relative to the injection hole.

7. The steering column according to claim 6, wherein: A ramp extends into the injection hole so that when the first sheath is compressed relative to the second sheath along axis (A), the ramp guides the lower head out of the connector opening.

8. The steering column according to claim 7, wherein: The slope portion extends from an outer surface of the first sheath toward the retaining groove and into the injection hole.

9. The steering column according to claim 8, wherein: The slope portion is in a semi-bowl shape.

10. The steering column according to claim 1, wherein The at least one connector comprises a rivet.

11. The steering column according to claim 1, wherein The at least one connector opening includes a pair of connector openings with injection holes, and the at least one connector includes a pair of connectors.

12. An axially adjustable steering column, comprising: a first sheath and a second sheath, wherein the second sheath is axially movable relative to the first sheath; The first sheath includes at least one connector opening; an energy absorbing assembly comprising a strap body connected to the first jacket by at least one fastener extending through the strap body and the at least one connector opening, The second jacket includes a window, and the energy absorbing assembly includes a locking cam at least partially located in the window and connected to the second jacket.

13. The steering column according to claim 12, wherein: The locking cam includes a toothed portion that selectively engages the strap body.

14. An energy absorbing assembly for an axially adjustable steering column, the energy absorbing assembly comprising: a strap body extending between a first end and a second end, the first end being configured to be positioned exteriorly of the first sheath and the second end being configured to be positioned interiorly of the first sheath; a curved portion located between the first end and the second end; a first segment and a second segment, the first segment extending between the curved portion and the first end, and the second segment extending between the curved portion and the second end; The first section includes at least one upper hole for receiving a fastener to connect the first section to the exterior of the first sheath, wherein the first segment defines a plurality of teeth; Wherein, the at least one upper hole comprises a pair of upper holes, wherein each upper hole is located on opposite sides of the tooth.

15. The energy absorbing assembly of claim 14, wherein: The second section includes a lower hole for receiving the rivet tip prior to deformation of the rivet tip.

16. The energy absorbing assembly of claim 14, wherein: The second segment includes an arcuate portion extending toward the first segment.

17. An energy absorbing assembly for an axially adjustable steering column, the energy absorbing assembly comprising: a strap body extending between a first end and a second end, the first end being configured to be positioned exteriorly of the first sheath and the second end being configured to be positioned interiorly of the first sheath; a curved portion located between the first end and the second end; a first segment and a second segment, the first segment extending between the curved portion and the first end, and the second segment extending between the curved portion and the second end; The first section includes at least one upper hole for receiving a fastener to connect the first section to the exterior of the first sheath, The fastener is located in the upper hole and is configured to be ejected from the opening with the slope in the first sheath to be disconnected therefrom.

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