Auxiliary un-retracting mechanism for a vehicle steering column

Abstract

An assisted stow mechanism for a vehicle column includes a telescoping actuator assembly. The assisted stow mechanism further includes a first electronic control unit (ECU) in communication with the telescoping actuator assembly to control the telescoping actuator assembly. The assisted stow mechanism further includes a latch actuator operable to control a latch assembly that controls a locked state and an unlocked state of an axial position of the vehicle column. The assisted stow mechanism further includes a second ECU in communication with the first ECU and the latch actuator, the second ECU controlling the latch actuator.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Patent Application Serial No. 63 / 280,210, filed November 17, 2021, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The embodiments disclosed herein relate to vehicle steering column assemblies, and more specifically, to auxiliary unstowing mechanisms for such assemblies. Background Technology

[0004] Retractable steering column systems for highway vehicles are designed to provide greater convenience to the user in certain situations by offering more space around the vehicle occupant. The column allows the steering wheel to retract toward or into the vehicle's dashboard when appropriate. This may be desirable, for example, when the vehicle is parked. If the vehicle has the ability to be autonomously operated in one or more driving modes, and can also be operated by the user in one or more driving modes, then this stow feature can be used when the vehicle is being driven autonomously or semi-autonomously.

[0005] Due to a system malfunction, the steering column may fail to retract (unload). If the steering column cannot retract, the user may no longer be able to properly operate the vehicle. This could be due to the steering wheel being in an extreme position or too close to the dashboard, preventing the user from maneuvering the vehicle. Alternatively, the vehicle may not allow the user to turn the steering wheel when it is in a specific area within the steering column's full range of motion. If the vehicle cannot drive itself to the user's desired destination, the user may need to immediately request towing and repairs. The inability to drive the vehicle can cause significant inconvenience.

[0006] In one example of a power steering column topology, a first electronic control unit (ECU) controls the telescope motor. When fully retracted, and during a malfunction of the first ECU or the telescope control, the driver is unable to operate the vehicle. Summary of the Invention

[0007] According to one aspect of the disclosure, an assisted undocking mechanism for a vehicle column includes a telescoping actuator assembly. The assisted undocking mechanism also includes a first electronic control unit (ECU) in communication with the telescoping actuator assembly to control the telescoping actuator assembly. The assisted undocking mechanism also includes a latch actuator operable to control a latch assembly that controls a locked state and an unlocked state of an axial position of the vehicle column. The assisted undocking mechanism also includes a second ECU in communication with the first ECU and the latch actuator, the second ECU controlling the latch actuator.

[0008] According to another aspect of the disclosure, a method of undocking a vehicle column is provided. The method includes operating a telescoping actuator assembly with a first electronic control unit (ECU). The method also includes operating a latch actuator with a second ECU. The method also includes monitoring the first ECU with the second ECU to monitor the first ECU and / or the telescoping mechanism for a fault condition.

[0009] These and other advantages and features will become more apparent from the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0010] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the claims attached to this 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:

[0011] Figure 1 is a schematic view of a steering column assembly with an assisted undocking mechanism;

[0012] Figure 2 is an elevational view of the steering column assembly;

[0013] Figure 3 is a cross-sectional view of a portion of the steering column assembly;

[0014] Figure 4 is a schematic view of an assisted undocking mechanism for the steering column assembly;

[0015] Figure 5 is a schematic view of an assisted undocking mechanism according to another aspect of the disclosure; and

[0016] Figure 6 is a flowchart of the operation of the assisted undocking mechanism of the steering column assembly. DETAILED DESCRIPTION

[0017] Reference will now be made to the drawings wherein illustrated embodiments of the invention will be presented by way of example, but not limitation, as follows: Figure 1A steering column assembly 20 is shown. The steering column assembly 20 facilitates the retraction and translation of a steering wheel (not shown) and a steering shaft 26 in a retractable manner. This is particularly advantageous in embodiments where the assembly 20 is used in passenger vehicles equipped with advanced driver assistance systems (ADAS) to allow for autonomous or semi-autonomous control of the vehicle using sensing, maneuvering, and / or braking technology. When the ADAS is actuated, vehicle control with the steering wheel is not required in some situations. Retraction of the steering wheel and steering shaft 26 toward (and possibly into) the dashboard greatly improves user comfort by providing more space for the driver. The additional space provided is advantageous for, e.g., additional workspace area or legroom.

[0018] Embodiments described herein provide for retractable steering columns that allow for the retraction of a steering wheel when the vehicle is in autonomous or semi-autonomous driving mode, and methods related to monitoring and adjusting the steering column assembly 20. Retraction of the steering column assembly 20 (and steering wheel) toward (and possibly into) the dashboard can be referred to as a "stowed" position or "stowed" state; meanwhile, extension of the steering column assembly 20 to a range of positions that allow for manual manipulation of the vehicle by an operator can be referred to as an "unstowed" position or "unstowed" state. While the steering column assembly 20 can be in the stowed position in autonomous or semi-autonomous driving mode, other situations for the stowed steering column assembly 20 are contemplated. For example, a parked vehicle can allow for the steering column assembly 20 to be positioned in the stowed position.

[0019] The electric motor 48 of the telescoping actuator assembly 22 at least partially retracts and extends the steering column assembly 20 into and out of the dashboard of the vehicle. However, embodiments described herein allow for manual adjustment in some situations, as described herein.

[0020] Extension and retraction of the steering column assembly 20 refers to the translation of the retractable portion 28 of the steering column assembly 20. The retractable portion 28 includes one or more translatable components. For example, in addition to the steering wheel and steering shaft 26 described above, a movable portion (which can also be referred to as an upper shroud in some embodiments) 28 can translate relative to a fixed portion (which can be referred to as a lower shroud in some embodiments) 24. A mounting bracket 25 is also shown that couples the steering column assembly 20 to the vehicle. In other embodiments, more or fewer than two shrouds are provided.

[0021] Figure 2 and Figure 3 Embodiments of various features of the telescoping actuator assembly 22 that facilitate adjustment of the steering column assembly 20 are shown. Various embodiments of clutching devices and nuts are described in detail in U.S. Patent Application No. 15 / 628,836, which is incorporated by reference herein in its entirety.Figure 2 and Figure 3 Examples of such features are shown, but it is understood that the embodiments described herein apply to any power steering column that allows for manual adjustment under certain conditions, which are defined herein.

[0022] Figure 2 and Figure 3 A screw or threaded rod 44, a shuttle assembly 46, and an electric motor 48 are shown. The shuttle assembly 46 can include a shuttle 47 and a clutch device 58 that can be directly supported by and engaged with the shuttle 47, or a housing 56 of the shuttle 47.

[0023] The shuttle 47 of the shuttle assembly 46 can be mounted between the screw 44 and the E / A belt 29. More specifically, the shuttle assembly 46 is threadably mounted to the screw 44 so as to translate axially along the screw, and can be rigidly fixed to the E / A belt 29. In operation, and when the electric motor 48 rotates the screw 44, the shuttle assembly 46 translates axially along the rotating screw 44. During this axial translation, the rearward shaft portion 32 of the steering shaft 26 and the upper boot 28 are carried by the shuttle assembly 46 and translate therewith.

[0024] The shuttle assembly 46 can further include a nut or fixture 50, at least one bearing 52, at least one resilient member 54 (e.g., a coil spring or a leaf spring), and a housing 56. The screw 44 can be mounted to rotate about a centerline 59 to the lower boot 24, can not be mounted to translate axially along the lower boot 24, but is rotatably driven by the electric motor 48, which can be rigidly mounted to the stationary lower boot 24. The centerline 59 can be spaced apart from and substantially parallel to the axis 42.

[0025] The clutch device 58 can be mounted to the housing 56 and facilitates rotational disengagement of the nut 50 from the housing 56 (and / or the shuttle 47). The clutch device 58 can include an electric servo 60 and a bolt 62. The servo 60 can be mounted to an exterior of the housing 56, and its function is to move the bolt 62 into and out of at least one recess 64 defined by an exterior and circumferentially continuous surface of the nut 50. In one example, the recess 64 can be an axially extending groove. The clutch device 58, including the electric servo 60 and the bolt 62, can be collectively referred to herein as a “latch” or “latch assembly,” and is designated by the numeral 80.

[0026] In the present embodiment, the housing 56 can be an integral part (i.e., single piece) of the shuttle assembly 46 and thus translates axially with the shuttle assembly 46. The nut 50, bearings 52, and springs 54 can be mounted to the screw 44 within the housing 56. The nut 50 is threaded to the screw 44 such that rotation of the screw 44 about the centerline 59 causes the housing 56 and shuttle assembly 46 to translate axially along the screw 44. The first bearing 52 can be positioned axially between the first spring 54 and the forward end (i.e., annular face) of the nut 50. The second bearing 52 can be positioned axially between the second spring 54 and the rearward end of the nut 50.

[0027] In operation, and when the steering column assembly 20 is in the powered state and the clutch device 58 is engaged, the forward and rearward bearings 52 minimize any friction generated between the springs 54 and the respective ends of the nut. The axial force exerted on the screw 44 by the torque applied by the electric motor 48 when in the powered state is insufficient to overcome the compression force of the springs 54 (i.e., the springs are not axially compressed).

[0028] When the steering column assembly 20 is in the disengaged state (i.e., not powered by the electric motor 48), the clutch device 58 is not engaged (i.e., the servo 60 is disengaged). Manual axial force generated by the driver to axially extend or retract the steering column assembly 20 can cause the nut 50 to freely spin (i.e., spin backwards) on the now stationary screw 44, moving the shuttle assembly 46 axially.

[0029] The embodiments disclosed herein provide a steering column system that allows a user to still drive a vehicle after a failure of the telescoping mechanism of the steering column. The embodiments disclosed herein provide an alternative way to disengage the steering column without the need for a functioning telescoping actuator or its associated wiring harness, controller, power supply, or communication bus.

[0030] Reference is made to Figure 4, the steering input device 42 is shown in the stowed or partially stowed position. Axial or telescoping movement is assisted by the telescoping actuator assembly 22. The telescoping actuator assembly 22 is at least partially controlled by a first ECU (ECU1). Embodiments disclosed herein include a second ECU (ECU2) that is in wired or wireless communication with the first ECU. The second ECU powers and controls the latch assembly 80. The latch actuator 60 allows the release of the latch 80 that would otherwise prevent telescoping movement of the steering column assembly 20. In other words, the latch actuator 60 controls the engagement or disengagement (disconnection) of the latch 80. In some embodiments, the latch actuator 60 is a motor, but other types of actuators are also contemplated. In the engaged position, the steering column assembly 20 is locked in the stowed or partially stowed position. In the disengaged position, the steering column assembly 20 is movable to the un-stowed position. In some embodiments, the latch actuator 60 controls the bolt 62 that engages with the nut 50 of the clutch device 58.

[0031] While the steering column assembly 20 is stowed, partially stowed, the second ECU monitors the status of the first ECU with one or more signals and is able to detect a failure of the telescoping mechanism 22 or the first ECU. During a failure, the second ECU allows the latch function to be achieved by the latch actuator 60 so that the user can perform the un-stow operation and drive the vehicle. A failure to un-stow can be due to a failure of one or more components of the electromechanical system (e.g., the telescoping actuator assembly 22) required to perform the un-stow operation. Examples of such components include the telescoping electric motor 48, the ECU (ECU1) that controls the telescoping motor, the battery that powers the ECU1, the wiring harness, and / or the gears.

[0032] Figure 5 Embodiments are shown with a second ECU that has direct communication (wired or wireless) with the telescoping actuator assembly 22 in addition to the first ECU. This provides the second ECU the ability to directly monitor the telescoping actuator assembly 22 and the first ECU for failure conditions of the telescoping actuator assembly 22 or the first ECU.

[0033] As mentioned above, the stow feature described above can be used when the vehicle is parked or when advanced autonomous driving features are engaged (e.g., autonomous or semi-autonomous driving modes).

[0034] Reference is now made to Figure 6 A method of providing an assisted un-stow capability for a steering column is illustrated by a flowchart. In particular, an ECU (e.g., ECU2) that controls the latch actuator 60 receives a signal from the telescoping control ECU (e.g., ECU1) to evaluate whether the latch control should be activated.

[0035] While the application has been described in detail with respect to only a limited number of exemplary embodiments, it will be understood that the application is not limited to such embodiments. Rather, it will be appreciated that the application can be modified, altered, changed, supplemented, or otherwise adapted in any number of ways, all of which are intended to be within the scope and spirit of the application. Furthermore, while various non-limiting exemplary embodiments of the application have been described, it will be understood that various aspects of the application can include only some of these embodiments. Accordingly, the application should not be seen as being limited by the foregoing description.

Claims

1. An auxiliary retraction mechanism for a vehicle steering column, the auxiliary retraction mechanism comprising: Telescopic actuator assembly; A first ECU communicates with the telescopic actuator assembly to control the telescopic actuator assembly; A latch actuator that operatively controls a latch assembly, the latch actuator controlling the locked and unlocked states of the axial position of the vehicle steering column; as well as The second ECU communicates with the first ECU and the latch actuator, and the second ECU controls the latch actuator; Wherein, when the vehicle steering column is in the retracted or partially retracted position, the latch assembly is in the locked state to prevent manual adjustment of the vehicle steering column, and wherein, when the latch assembly is in the unlocked state, manual adjustment of the vehicle steering column is permitted. When the second ECU detects that the first ECU is in a fault state, the latch assembly is switched to the unlocked state by the latch actuator.

2. The auxiliary unpacking and storage mechanism according to claim 1, wherein, The second ECU communicates directly with the telescopic actuator assembly.

3. The auxiliary unpacking and storage mechanism according to claim 2, wherein, When the second ECU detects that the telescopic actuator assembly is in a faulty state, the latch assembly is switched to the unlocked state by the latch actuator.

4. The auxiliary unpacking and storage mechanism according to claim 1, wherein, The telescopic actuator assembly includes: A nut, operatively threadedly connected to a screw for translational movement between the screw and the nut; The housing is operatively engaged with the nut; The bearing is operatively disposed between the housing and the nut.

5. The auxiliary unpacking and storage mechanism according to claim 4, wherein, The bearing in question is a clutch bearing.

6. The auxiliary unpacking and storage mechanism according to claim 4, wherein, The telescopic actuator assembly also includes an elastic member disposed axially between the bearing and the housing.

7. The auxiliary unpacking and storage mechanism according to claim 4, wherein, The housing is a shuttle, and the telescopic actuator assembly further includes a clutch device that engages with the shuttle and is configured to lock the shuttle to the nut.

8. The auxiliary unpacking and storage mechanism according to claim 7, wherein, The clutch assembly includes a bolt disposed within a groove in the nut to lock the shuttle portion to the nut.

9. A method for retracting and storing a vehicle steering column, comprising: The telescopic actuator assembly is operated via the first ECU; The latch actuator is operated via the second ECU; The first ECU is monitored by the second ECU to monitor the fault status of the first ECU and / or the telescopic actuator assembly; as well as When the second ECU detects that the first ECU is in the fault state, it unlocks the latch assembly through the latch actuator.

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