Patent Publication Number: US-2023159082-A1

Title: Steering column energy absorption strap assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefits of priority to U.S. patent application Ser. No. 63/281,429, filed Nov. 19, 2021, the disclosure of which is incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The embodiments disclosed herein relate to vehicle steering column assemblies and, more particularly, to an energy absorption strap assembly for such assemblies. 
     BACKGROUND 
     A steering column assembly of a vehicle may include one or more energy absorption features. For example, an energy absorption strap (EA strap) assembly may be operatively coupled to an upper jacket and configured to unroll once a specified collapse load is exceeded. EA straps have been configured to fit inboard (i.e., radially or laterally inward) of a rake bracket. This configuration has packaging constraints with respect to upper jacket outer diameter limitations. 
     SUMMARY OF THE DISCLOSURE 
     According to one aspect of the disclosure, a steering column assembly includes a lower jacket. The steering column assembly also includes an upper jacket operatively coupled to the lower jacket, the upper jacket telescopingly moveable relative to the lower jacket. The steering column assembly further includes a rake bracket operatively coupled to the lower jacket. The steering column assembly yet further includes an energy absorption strap operatively coupled to the upper jacket, at least a portion of the energy absorption strap disposed radially outward of the rake bracket. 
     According to another aspect of the disclosure, a steering column assembly includes a manual rake adjustment assembly. The manual rake adjustment assembly includes a rake lever. The manual rake adjustment assembly also includes a rake bolt operatively coupled to the rake lever and rotatable therewith, the rake bolt extending through a first rake bracket leg and a second rake bracket leg. The steering column assembly also includes an energy absorption strap. The energy absorption strap includes a first leg. The energy absorption strap also includes a second leg extending substantially parallel to the first leg. The energy absorption strap further includes a curved portion connecting the first leg and the second leg. The second leg is disposed radially outward of the rake bracket. 
     These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The subject matter that is regarded as the subject 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 are apparent from the following detailed description of non-limiting exemplary embodiments of the invention taken in conjunction with the accompanying drawing thereof in which: 
         FIG.  1    is a perspective view of a steering column assembly; 
         FIG.  2    is a side, elevational view of the steering column assembly; 
         FIG.  3    is a perspective view of a portion of the steering column assembly where an energy absorption strap assembly is located; 
         FIG.  4    is a perspective view of the energy absorption strap assembly with a strap cover removed; and 
         FIG.  5    is a side, elevational view of the energy absorption strap assembly with the strap cover removed. 
     
    
    
     DETAILED DESCRIPTION 
     The embodiments described herein may be utilized in a vehicle, such as a car, truck, sport utility vehicle, crossover, mini-van, marine craft, aircraft, all-terrain vehicle, recreational vehicle, or other suitable vehicle, include various steering system schemes, for example, steer-by-wire and driver interface steering. These steering system schemes typically include a steering column for translating steering input to an output that interacts with a steering linkage to ultimately cause the vehicle wheels (or other elements) to turn the vehicle. 
     Referring now to the Figures,  FIGS.  1 - 3    illustrate a steering column assembly generally indicated with numeral  10 . The steering column assembly  10  is for a vehicle and extends along a longitudinal axis X. The steering column assembly  10  may be adjustable in a telescopic direction generally parallel with the longitudinal axis X (i.e., adjustable along the longitudinal axis X), and adjustable in a rake direction that moves the steering column upward or downward. The steering column assembly  10  includes a lower jacket  12  and an upper jacket  13  extending along the longitudinal axis X. The upper jacket  13  has a portion extending into the lower jacket  12  and is translatable relative thereto. 
     The translatable motion of the upper jacket  13 , relative to the lower jacket  12 , allows the upper jacket—and a steering input device (e.g., handwheel) operatively coupled thereto—to be axially adjustable between positions to provide flexibility in the location of a steering input device and facilitate more comfortable driving positions for different sizes of drivers. The axial adjustment may be carried out with an electromechanical system or manually by an operator. 
     Rake movement of the upper jacket  13  and at least a portion of the lower jacket  12  allows the steering input device to be rotated about one or more pivot points to adjust a vertical position of the steering input device. The rake movement may also be carried out with an electromechanical system or manually by an operator. In the illustrated embodiment, a manually rake adjustable embodiment is shown. In such an embodiment, a rake lever  80  is operatively coupled to a rake bolt  82  which extends through a first rake bracket leg  84 , the lower jacket  12 , the upper jacket  13 , and a second rake bracket leg. Adjustment of the rake lever  80  changes a clamp load with a cam assembly or the like to move the rake adjustment assembly between a locked condition and an unlocked condition, with the unlocked condition allowing manual rake adjustment. 
     An energy absorption strap assembly (EA strap assembly)  20  is operatively coupled to the steering column assembly  10  to assist with the energy absorption process during a collapse event of the steering column assembly  10 . The EA strap assembly  20  includes a strap cover  40  that is operatively coupled to a radially outer surface of the lower jacket  12 . In the illustrated embodiment, the strap cover  40  includes a longitudinally extending base segment  42  and a pair of legs  44  on each side of the base segment  42 . Each of the legs  44  extend inwardly toward the lower jacket  12  and are connected to the lower jacket  12  in any suitable manner. In the illustrated embodiment, the legs  44  include flanges  46  that align with receiving holes defined by the lower jacket  12 , with mechanical fasteners  48  extending through the flanges  46  to couple the cover  40  to the lower jacket  12 . 
     Referring now to  FIGS.  4  and  5   , the strap cover  40 —which covers at least a portion of an energy absorption strap (EA strap)  22 —has been removed to more clearly illustrate the EA strap  22 . The EA strap  22  includes a first leg  24  and a second leg  26  which are joined by a curved, transition portion  28 . The first leg  24  is fixed to the upper jacket  13  and rolls during an energy absorption event. The first leg  24  may be joined to the upper jacket  13  in any suitable manner. In the illustrated embodiment, a mechanical fastener  29  extends through the first leg  24  and into the upper jacket  13  to fix the EA strap  22  to the upper jacket  13 . A spacer  27  or other structural component may facilitate the coupling as well, as shown. The coupling location of the first leg  24  of the EA strap  22  and the upper jacket  13  is within a cutout portion  32  of the lower jacket  12 . 
       FIGS.  1 - 5    each illustrate the second leg  26  of the EA strap  22  extending away from the curved, transition portion  28  to a terminal end  34  of the second leg  26 . The second leg  26  is substantially straight and extends substantially parallel to the first leg  26 . The terminal end  34  of the second leg  26  of the EA strap  22  protrudes in axial overlap with one of the rake bracket legs. In the illustrated configuration, the portion of the second leg  26  proximate the terminal end  34  is in axial overlap with the first rake bracket leg  84 , but it is to be appreciated that the EA strap assembly  40  may be positioned on an opposite side of the steering column assembly  10 , such that the EA strap  22  is in axial overlap with the second rake bracket leg. Regardless of the rake bracket leg that the second leg  26  overlaps with, it is to be understood that the second leg  26  is located radially outward (which may also be referred to as laterally outward) relative to the first rake bracket leg  84 . 
     Advantageously, the embodiments disclosed herein avoid packaging constraints that were previously present in assemblies that had an EA strap radially inward of the rake bracket. Additionally, the disclosed configuration allows for a larger upper jacket outer diameter for cross-car packaging and instrument panel attachment of the steering column since the space radially—or laterally—inward of the rake bracket leg is not taken up with the EA strap  22 . 
     While the invention has been described in detail in connection with only a limited number of exemplary embodiments, it should be appreciated that the invention is not limited to such embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions, or equivalent arrangements not heretofore described, but that are commensurate with the spirit and scope of the invention. Additionally, while various non-limiting exemplary embodiments of the invention have been described, it should be appreciated that aspects of the invention may include only some of these embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description.