Patent ID: 12227224

DETAILED DESCRIPTION

The following discussion is directed to various embodiments of the disclosure. Although one or more of these embodiments may be described in more detail than others, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.

As described, a vehicle, such as a car, truck, sport utility vehicle, crossover, mini-van, marine craft, aircraft, all-terrain vehicle, recreational vehicle, or other suitable vehicles, 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. Some steering columns are axially adjustable between positions. In the past, a function of axially adjustable steering columns was to provide flexibility in the location of the hand wheel and facilitate more comfortable driving positions for different sizes of drivers. However, now there are opportunities for significantly more telescopic travel, which also may be referred to as stow travel (i.e., when the hand wheel is not needed). For example, the hand wheel could be repositioned completely away from the driver to allow him or her to do things other than operate the vehicle, such as work on a laptop computer when the vehicle is parked. Other examples include vehicles with autonomous driving capability, such that the hand wheel could be stowed when the vehicle is in an autonomous driving mode.

Referring now to the drawings, where the various embodiments are shown and described herein without limiting same,FIGS.1-4Billustrate embodiments of a steering column assembly that is axially adjustable with improved packaging and other operational benefits. The axial adjustability results from relative movement between two steering column portions (e.g. jackets, brackets, rails, and/or the like) which permit axial movement therebetween. In the disclosure, the term “jacket” is used to represent any form of column portions. In particular, an upper jacket and a lower jacket will be referenced and is illustrated in the drawings. The specific terminology is not limiting of the particular type of steering column portions contemplated within the scope of the disclosure.

In some embodiments, the relative movement between the column portions work in combination with relative movement between multiple steering shaft portions that permit axial movement therebetween. Axial movement refers to movement resulting from relative telescopic, sliding, and/or translational movement between components in a longitudinal direction of the overall steering column assembly.

Referring initially toFIG.1, a vehicle20is generally illustrated according to the principles of the present disclosure. The vehicle20may include any suitable vehicle, such as a car, a truck, a sport utility vehicle, a mini-van, a crossover, any other passenger vehicle, any suitable commercial vehicle, or any other suitable vehicle. While the vehicle20may be a passenger vehicle having wheels and for use on roads, the principles of the present disclosure may apply to other vehicles, such as planes, tractors, boats, or other suitable vehicles. The vehicle20may include a propulsion system30, such as an ignition system, an electronic system, or combinations thereof.

In some embodiments, the vehicle20may further include a steering system40. The steering system40may be configured as a driver interface steering system, an autonomous driving system, or a system that allows for both driver interface and autonomous steering. The steering system may include an input device42, such as a steering wheel, wherein a driver may mechanically provide a steering input by turning the steering wheel. A steering column assembly44includes a steering column45that extends along an axis from the input device42to an output assembly46. The output assembly46is part of a steer-by-wire and/or autonomous driving system. The output assembly46may be referred to as an emulator and is used to provide feedback to the steering input device42and to receive manual driver inputs for steering control.

The steering column45includes two axially adjustable portions, for example, an upper jacket48and a lower jacket50that are axially adjustable with respect to one another.

The steering column45is moveable between a range of positions from a fully extended position to a fully retracted position. In the fully extended position, the upper jacket48is moved axially with respect to the lower jacket50so that the input device42is located near an operator of the vehicle. In the retracted position, the upper jacket48is moved axially with respect to the lower jacket50so that the input device42is located further away from an operator of the vehicle, when compared to the extended position. In some embodiments, the retracted position may correspond to stowing the input device42. For example, it may be beneficial to place the input device42in a stowed location during autonomous driving. In operation, axial movement between the upper jacket48and the lower jacket50is effectuated electromechanically by one or more actuators. This axial movement adjusts between the extended position, the retracted position, and any intermediary positions. As described in detail below, the steering column is moveable in an axial direction over a first range of positions and over a second range of positions.

A steering gear assembly54may connect to the output assembly46via a steering gear input shaft56. The steering gear assembly54may be configured as a rack-and-pinion, a recirculating ball-type steering gear, or any other types of steering gears associated with autonomous and driver-interface steering systems. The steering gear assembly54may then connect to a driving axle58via an output shaft60. The output shaft60may include a pitman arm and sector gear and/or various traditional components. The output shaft60is operably connected to the steering gear assembly54such that a rotation of the steering gear input shaft56causes a responsive movement of the output shaft60and causes the drive axle to turn wheels62.

With reference now toFIGS.2and3, the steering column assembly44is illustrated in greater detail. The upper jacket48is shown protruding from the lower jacket50. The lower jacket48is operatively coupled to, and axially translatable relative to, a column mounting bracket70. The column mounting bracket70is fixed relative to a vehicle structure to mount the steering column assembly44to the vehicle. The emulator46is at least partially positioned within a handwheel feedback actuator housing76. The handwheel feedback actuator housing76is operatively coupled to the lower jacket50in a manner that allows the housing76to axially travel with the lower jacket50in operation. In the illustrated embodiment, the handwheel feedback actuator housing76is coupled to a forward end of the lower jacket50.

The upper jacket48is axially adjustable relative to the lower jacket50over a first range of axial positions, which may be referred to as a “comfort range”. The comfort range is a range of axial positions that are useful for manual driving during operation of the vehicle for different sized operators. The axial movement of the upper jacket48relative to the lower jacket50is done in a telescoping manner due to the movement of the upper jacket48within the lower jacket50. The comfort range encompasses a range of axial positions which are useful for an operator during a manual driving mode of the vehicle. In other words, the steering input device42is accessible and able to be comfortably controlled over the first range of axial positions.

The second range of axial positions may be referred to as a “stowing range” of the steering column45. The stowing range is a range of axial positions that moves the overall steering column assembly further away from the operator when compared to the comfort range (i.e., toward an instrument panel and firewall of the vehicle). In some embodiments, the fully retracted position is a stowed position that may be flush with an instrument panel, firewall or other vehicle structure. The stowing range of axial movement includes further telescope travel of the upper jacket48relative to the lower jacket, in combination with axial movement of the lower jacket50relative to the column mounting bracket70. The movement of the lower jacket50relative to the column mounting bracket70is done in a translating manner due to the movement of the overall upper and lower jackets together adjacent to the column mounting bracket70.

FIGS.4A and4Billustrate the steering column assembly44in two axial positions. In particular,FIG.4Ashows the steering column assembly44in a non-stowed position where the upper jacket48is extended within the first range of axial positions.FIG.4Bshows the steering column assembly44in a stowed position where the upper jacket48is positioned in a full telescope-in location relative to the lower jacket50, and the lower jacket50is translated fully away from the operator relative to the column mounting bracket70.

With continued reference toFIGS.2and3, the steering column assembly44includes a first actuator72which may be referred to as a comfort/stow actuator. The first actuator72is operatively coupled to the upper jacket48to control the telescoping movement of the upper jacket48relative to the lower jacket50over the first range of axial positions. In the illustrated embodiment, the first actuator72is mounted to a specific portion of the steering column assembly44, but other mounting locations are contemplated.

The steering column assembly44also includes a second actuator74which may be referred to as a stowing actuator. The second actuator74is operatively coupled to the lower jacket50to control the translating movement of the lower jacket50relative to the column mounting bracket70over the second range of axial positions. In the illustrated embodiment, the second actuator74is mounted to a specific portion of the steering column assembly44, but other mounting locations are contemplated.

Both the first and second actuators are located proximate a forward location of the steering column assembly44to accommodate the axial movement during a stowing operation. The term “forward” refers to a position relative to the vehicle that the steering column assembly44is disposed within and distal relative to the input device42. The two actuators72,74are responsible for the full stow motion of the steering column45, however only the first actuator72operates during comfort adjustment within the first range of axial adjustment positions. In other words, the first actuator72is solely responsible for axial adjustment over the first range, but the first actuator72and the second actuator74operate simultaneously during the stowing which occurs over the second range of travel. The first actuator72is affixed between the upper jacket48and the lower jacket50, while the second actuator74is affixed between the column mounting bracket70and the lower jacket50. In some embodiments, the actuators72,74may each be fixed to the handwheel feedback actuator housing76, which houses the emulator46.

Each actuator72,74, may cause axial movement of the respective associated components it is operatively coupled to. By way of non-limiting example, the illustrated embodiment of each actuator72,74includes an electric motor that has an output shaft coupled to a lead screw. The lead screw has a nut threaded thereto, such that rotation of the lead screw results in axial translation of the nut since the nut is rotatably constrained. The respective nut of each actuator72,74is operatively coupled to a component that drives axial movement of the component during operation. In particular, the nut of the first actuator72results in axial movement of the upper jacket48relative to the lower jacket50, while the nut of the second actuator72results in axial movement of the lower jacket50relative to the column mounting bracket70.

Additionally, a rake actuator assembly80is mounted to the lower jacket50, as shown well inFIG.3. The rake actuator assembly80controls movement in a rake direction of the steering column assembly44. The rake actuator assembly80includes a rake bracket82that is operatively coupled to the lower jacket50and adjusts the steering column45substantially vertically about a pivot axis located proximate a forward location of the steering column assembly44.

As shown inFIGS.2,4A and4B, the column mounting bracket70defines a first set of tapered rail slots90. Referring toFIGS.3,4A and4B, the lower jacket50defines a second set of tapered rail slots92. The first set of tapered rail slots90extends longitudinally in an axial direction of the steering column45and includes a slot on each lateral side of the column mounting bracket70. The second set of tapered rail slots92extends longitudinally in an axial direction of the steering column45and includes a slot on each lateral side of the lower jacket50. The tapered slots of the first set of tapered rail slots90each tapers from a widest dimension at a laterally outward location of the column mounting bracket70to a narrower dimension at a laterally inward location of the column mounting bracket70. The tapered slots of the second set of tapered rail slots92each tapers from a widest dimension at a laterally outward location of the lower jacket50to a narrower dimension at a laterally inward location of the lower jacket50. The relative elevations of the first and second sets of tapered rail slots90,92may vary.

Referring toFIGS.2and3, the steering column assembly44is installed to the column mounting bracket70and coupled thereto with bolts and sliding wedge bushings. In particular, a first pair of sliding wedge bushings94is positioned within the first set of tapered rail slots90, with one sliding wedge bushing on each side of the column mounting bracket70. Each of the first pair of sliding wedge bushings94is coupled to the rake bracket82with a first set of bolts96. The first pair of sliding wedge bushings94are positioned at an outward location of the column mounting bracket70and the bolts96extend through the first sliding wedge bushings94and into the rake bracket82. The rake bracket82is coupled to the lower jacket50with one or more mechanical fasteners93on each side of the lower jacket50.

Referring now toFIGS.3,4A and4B, a second interface between the lower jacket50and the column mounting bracket70is provided with a second pair of sliding wedge bushings98. The second pair of sliding wedge bushings is positioned within the second set of tapered rail slots92, with one sliding wedge bushing on each side of the lower jacket50. The second pair of sliding wedge bushings98are positioned at an outward location of the lower jacket50and coupled to the column mounting bracket70with a pair of bolts100extending through the column mounting bracket70and the second sliding wedge bushings98. The tapered rail slots90,92in the column mounting bracket70and the lower jacket50serve as a receiving interface for the sliding wedge bushings94,98and provide guidance for the upper jacket48and the lower jacket50to translate relative to the column mounting bracket70during stow operation.

In some embodiments, the first and second sliding wedge bushings94,98constrict around the bolts or nuts associated therewith when driven into the tapered rail slots90,92on the column mounting bracket70and the lower jacket50, respectively, thereby de-lashing the joints.

The embodiments disclosed herein provide a stowable steering column assembly44that moves the forward-most point of the footprint away from a firewall during normal driving operation, thereby creating additional space for vehicle energy absorption during a barrier event. The disclosed embodiment allow for long displacement deep-stow functionality, while minimizing footprint size compared to other column designs, such as triple jacket designs, for the same stow displacement.

While the invention has been described in detail in connection with only a limited number of embodiments, it is to 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. Moreover, any feature, element, component or advantage of any one embodiment can be used on any of the other embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description.