Abstract:
According to one exemplary embodiment of the present invention a steering column assembly is provided. The steering column assembly includes a steering column shaft. The steering column assembly further includes a retraction actuator to translate an adjustment actuator mounting plate within a retraction range. The steering column further includes an adjustment actuator mounted on the adjustment actuator mounting plate to translate a steering column bracket within an adjustment range. The steering column bracket translates the steering column shaft within a steering column shaft movement range. The steering column shaft movement range is a sum of the retraction range and the adjustment range.

Description:
FIELD OF THE INVENTION 
     The following description relates to steering column assemblies and, more specifically, to a retractable steering column assembly. 
     BACKGROUND 
     When some vehicles are fitted with autonomous driving assist systems, it may become possible to retract and stow the steering column and wheel away from the driver to provide space for non-driving related activities such as working, reading, and game playing. However, if the autonomous driver assistance system relinquishes control, a typical return of the steering wheel to a driving position may be longer than needed for the driver to regain safe control. 
     Accordingly, it is desirable to provide a steering column assembly that enables the driver to rapidly return the wheel from a retracted position. 
     SUMMARY OF THE INVENTION 
     According to one exemplary embodiment of the present invention a steering column assembly is provided. The steering column assembly includes a steering column shaft. The steering column assembly further includes a retraction actuator to translate an adjustment actuator mounting plate within a retraction range. The steering column further includes an adjustment actuator mounted on the adjustment actuator mounting plate to translate a steering column bracket within an adjustment range. The steering column bracket translates the steering column shaft within a steering column shaft movement range. The steering column shaft movement range is a sum of the retraction range and the adjustment range. 
     In another exemplary embodiment of the present invention a method to deploy and retract a steering column shaft is provided. The method includes translating an adjustment actuator within a retraction range via a retraction actuator. The method further includes translating a steering column bracket within an adjustment range via the adjustment actuator. The method further includes translating a steering column shaft within a steering column shaft movement range via the steering column bracket. The steering column shaft movement range is a sum of the retraction range and the adjustment range. 
     In yet another exemplary embodiment of the present invention, a vehicle is provided. The vehicle includes a steering column assembly. The steering column assembly includes a steering column shaft, a column jacket, and a steering wheel. The steering wheel is coupled to the steering column shaft. The steering column assembly further includes a retraction actuator to translate an adjustment actuator mounting plate within a retraction range. The steering column further includes an adjustment actuator mounted on the adjustment actuator mounting plate to translate a steering column bracket within an adjustment range. The steering column bracket translates the steering column shaft within a steering column shaft movement range. The steering column shaft movement range is a sum of the retraction range and the adjustment range. 
     These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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 are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a schematic view of a vehicle and steering column assembly according to one embodiment of the disclosure; 
         FIG. 2  is a perspective view of a steering column assembly according to one embodiment of the disclosure; and 
         FIG. 3  is a plan view of the steering column of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the Figures, where the invention will be described with reference to specific embodiments, without limiting same,  FIG. 1  illustrates an exemplary vehicle  10 , such as an autonomous driving assisted steering (“ADAS”) equipped vehicle, generally having a retractable steering column assembly  14 . The steering column assembly  14  generally includes a steering column shaft  16  and a steering input device, such as steering wheel  18 , coupled thereto. 
     In the illustrated embodiment, steering column assembly  14  is movable between a retracted position  20 , and a deployed or driving position  22 . In the retracted position  20 , portions of assembly  14  such as steering wheel  18  are disposed away from the driver, which provides increased space for the driver. The displacement of the steering column shaft  16  and wheel  18  in retracted position  20  creates additional cabin space for the driver&#39;s comfort and convenience to perform non-driving activities including, but not limited to, reading, working, entertaining, eating, texting, etc. In the driving position  22 , steering wheel  18  may be used by a driver to steer the vehicle. In certain embodiments, the position of the steering column shaft  16  and the steering wheel  18  can be adjusted in the driving position  22  to provide a desired position for the driver. The adjustable driving position may be stored or otherwise recorded when returning from a retracted position  20  to a driving position  22 . 
     In certain embodiments, the steering wheel  18  can be automatically retracted in a retracted position  20  in response to the initiation of an autonomous driving event. Similarly, the steering wheel  18  can be extended to the driving position  22  to provide control to the driver at the termination of an autonomous driving event, or when an autonomous driving system requires the input of the driver. Accordingly, it may be desired to extend the steering wheel  22  to the driving position  22  rapidly to provide control to the driver as required. 
     Referring to  FIGS. 2 and 3 , an illustrated embodiment of the steering column assembly  210  is shown. In the illustrated embodiment, the steering column assembly  210  includes a steering column shaft  211 , a column jacket  212 , an assembly bracket  214 , an adjustment actuator  220 , and a retraction actuator  230 . The steering column assembly  210  can extend and retract the steering column shaft  211  rapidly to provide the driver access to the steering wheel as required. 
     In the illustrated embodiment, the column shaft  211  is attached to a steering wheel as shown in  FIG. 1 . The column shaft  211  includes a column jacket  212  disposed around the column shaft  211 . In the illustrated embodiment, the column shaft  211  can be telescoped or translated via the adjustment actuator  220  and the retraction actuator  230 . However, the column shaft  211  may also be movable in a rake or tilt direction. As shown in  FIG. 3 , the column shaft  211  has a steering column shaft movement range S to allow the column shaft  211  to translate or telescope. Advantageously, the steering column shaft movement range S allows for a steering wheel to be retracted when not in use and extended when required. Further, the steering column shaft movement range S allows for driver adjustability for a desired operating position. 
     In the illustrated embodiment, the adjustment actuator  220  includes a lead screw  221 , a steering column bracket  222 , a motor  223 , and an adjustment actuator mounting plate  224 . The adjustment actuator  220  allows for adjustments to the steering column shaft  211  in a deployed position and can be utilized to provide at least some of the retraction of the steering column shaft  211 . In the illustrated embodiment, the adjustment actuator  220  is mounted to the retraction actuator  230  via the adjustment actuator mounting plate  224  to allow the retraction actuator  230  to translate the adjustment actuator  220 , facilitating in series operation of the retraction actuator  230  and the adjustment actuator  220 . 
     In the illustrated embodiment, the adjustment actuator  220  is any suitable actuator to translate the steering column bracket  222 . In certain embodiments, the adjustment actuator  220  is a screw type actuator with a lead screw  221 . The lead screw  221  may be rotated via a motor  223 . In certain embodiments, the steering column bracket  222  is threadedly engaged to the lead screw  221  and translates along the lead screw  221  as the lead screw  221  rotates in either direction. A steering column bracket rail  226  may guide the steering column bracket  222 . 
     In the illustrated embodiment, the steering column bracket  222  is coupled to the steering column shaft  211  directly or via the column jacket  212 . The adjustment actuator  220  is configured to move the steering column bracket  222  along an adjustment range A. In certain embodiments, the adjustment actuator  220  translates the steering column bracket  222  at a rate of approximately 10-12 millimeters per second. The adjustment range A may extend between a minimum adjustment position A 1  and a maximum adjustment position A 2 . In certain embodiments, the adjustment range A can be from 40 to 60 millimeters. 
     Accordingly, the position of the steering column bracket  222  can be translated along the adjustment range A to provide a range of adjustment to the column shaft  211  and the attached steering wheel for driver comfort. In particular, the adjustment range A can provide for driver comfort when the steering column shaft  211  is in a generally deployed position. A desired position can be stored as memory position A m . 
     Additionally, the adjustment actuator  220  can retract the steering column bracket  222  toward the minimum adjustment position A 1  to provide the driver additional room when the column shaft  211  is in the retracted position. Advantageously, the adjustment actuator  220  can retract to the minimum adjustment position A 1  while the retraction actuator  230  is concurrently retracting to increase the overall speed of retraction of the column shaft  211 . In certain embodiments, the adjustment actuator  220  can utilize the user memory position A m  to maintain the adjustment position of the column shaft  211  after the shaft is retracted and then later redeployed. 
     In the illustrated embodiment, the retraction actuator  230  includes a lead screw  231 , a motor  233 , a retraction actuator mounting plate  234  and the adjustment actuator mounting plate  224 . The retraction actuator  230  generally allows the steering column shaft  211  to be translated from an at least partially retracted position to a deployed position. In the illustrated embodiment, the retraction actuator  230  can translate the adjustment actuator  220 , facilitating in series operation of the retraction actuator  230  and the adjustment actuator  220 . 
     In the illustrated embodiment, the retraction actuator  230  is any suitable actuator to translate the adjustment actuator mounting plate  224 . In the illustrated embodiment, the retraction actuator  230  is coupled to the assembly bracket  214  via the retraction actuator mounting plate  234 . In certain embodiments, the retraction actuator  230  is a screw type actuator with a lead screw  231 . The lead screw  231  may be rotated via a motor  233 . In certain embodiments, the adjustment actuator mounting plate  224  is threadedly engaged to the lead screw  231  and translates along the lead screw  231  as the lead screw  231  rotates in either direction. The mounting plate rail  236  may guide the adjustment actuator mounting plate  224 . 
     In the exemplary embodiment, the retraction actuator  230  is configured to move the adjustment actuator mounting plate  224  and the adjustment actuator  220  along the retraction range R. In certain embodiments, the retraction actuator  230  translates the adjustment actuator mounting plate  224  at a rate of approximately 10-12 millimeters per second. The retraction range R may extend between a retracted position R 1  and a deployed position R 2 . In certain embodiments, the retraction range R can be from 90 to 110 millimeters. Further, the position of the adjustable actuator mounting plate  224  can adjust the position of the steering column shaft  211  by translating the steering column bracket  222  of the adjustment actuator  220 . 
     Advantageously, the retraction actuator  230  can work in series with the adjustment actuator  220  to provide a rapid translation of the steering column shaft  211 . Further, the in series arrangement of the adjustment actuator  220  and the retraction actuator  230  can combine the operating ranges R and A to provide a total translation range S. The steering column shaft movement range S may extend between a fully retracted position S 1  and a fully extended position S 2 . In the illustrated embodiment, the steering column shaft movement range S may be between 130 and 170 millimeters. 
     Accordingly, since the adjustment actuator  220  and the retraction actuator  230  operate in series, the concurrent operation of the adjustment actuator  220  and the retraction actuation  230  allows double the translation rate while providing a wide range of translation within the steering column shaft movement range S. In the illustrated embodiment, the steering column shaft  211  can translate within the steering column shaft movement range S at a rate of approximately 20-24 millimeters per second. 
     During operation, the steering column shaft  211  can be retracted to place the steering wheel to a position S 1 . In certain embodiments, the steering column shaft  211  can be retracted during autonomous vehicle operation or any other suitable event. To facilitate retraction, the retraction actuator  230  can retract to a retracted position R 1 . Further, the adjustment actuator  220  can concurrently retract to a minimum extension position A 1 . Advantageously, since the adjustment actuator  220  and the retraction actuator  230  are operating in series the steering column shaft  211  can move more rapidly than if actuated by a single actuator. 
     During extension of the steering column shaft  211 , the steering column shaft  211  can extend from the fully retracted position S 1  to a desired position. In certain embodiments, the steering column shaft  211  can be extended at the termination of an autonomous vehicle operation or otherwise when driver input is required. In certain embodiments, the steering column shaft  211  is extended to toward the fully extended position S 2 . To facilitate extension, the retraction actuator  230  extends from the retracted position R 1  to the deployed position R 2 . Concurrently, the adjustment actuator  220  extends from the minimum extension A 1  towards a maximum extension A 2 . Advantageously, the use of both the adjustment actuator  220  and the retraction actuator  230  allows the steering column shaft  211  can extend rapidly. 
     In certain embodiments, during extension, the steering column shaft  211  can be extended to a preset memory position S m . In certain embodiments, the memory position A m  of the adjustment actuator  220  corresponds to the steering column shaft  211  memory position S m , when the retraction actuator  230  is fully deployed in position R 2 . 
     In certain embodiments, during extension of the steering column shaft  211 , the adjustment actuator  220  may extend to the memory position A m  before the retraction actuator  230  has fully deployed in position R 2 . In order to expedite the extension of the steering column shaft  211  to the memory position S m , the adjustment actuator  220  can continue to extend the column shaft bracket  222  beyond the A m  position, towards the maximum extension A 2  of the adjustment actuator  220 , to allow both actuators  220  and  230  to continue to extend the steering column shaft  211  in series. After the steering column shaft  211  has reached the desired memory position S m , the retraction actuator  230  can continue to extend to the deployed position R 2 , while the adjustable actuator  220  may reverse translation direction to reach the position A m , allowing the steering column shaft  211  to maintain the memory position S m . 
     While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while 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. Accordingly, the invention is not to be seen as limited by the foregoing description.