Locking mechanism for steering system

Abstract

Axially adjustable steering column, including: a first coat (48); a second jacket (50), wherein the first jacket (48) is axially adjustable relative to the second jacket (50); an adjusting lever (52); a locking mechanism (62), wherein the adjusting lever (52) selectively moves the locking mechanism (62) between a locked position and an unlocked position, wherein the locked position prevents axial adjustment of the first shell (48) relative to the second shell (50) in both axial directions and the unlocked position allows adjustment of the first shell (48) relative to the second shell (50), wherein the locking mechanism (62) comprises: an energy-absorbing belt (64) defining a first row of teeth (80) extending axially; a first cam (66) with a plurality of teeth (84) which, in the locked position, can be engaged with the first row of teeth (80) and, in the unlocked position, are disengaged from the first row of teeth (80), wherein the first cam (66) is rotatably mounted on a pin to allow the plurality of teeth (84) of the first cam (66) to rotate in and out of engagement with the first row of teeth (80) of the energy-absorbing belt (64); and a second cam (67) with a plurality of teeth (86), wherein the second cam (67) is mounted on a pin (94), characterized in that the energy-absorbing belt (64) defines a second row of teeth (82) extending axially, the first row of teeth (80) and the second row of teeth (82) are arranged on respective surfaces of the energy-absorbing belt (64) which are oriented perpendicular to each other, the multitude of teeth (86) of the second cam (67) can be engaged with the second row of teeth (82) in the locked position and are released from the second row of teeth (82) in the unlocked position, and the second cam (67) is mounted on the pin (94) to allow the multitude of teeth (86) of the second cam (67) to move in and out of engagement with the second row of teeth (82) of the energy-absorbing belt (64).

Description

TECHNICAL AREA

[0001] The following description relates to an axially adjustable steering column according to the preamble of claim 1, including a locking mechanism. BACKGROUND

[0002] A vehicle, such as a car, truck, SUV, crossover, minivan, personal watercraft, aircraft, all-terrain vehicle, recreational vehicle, or other suitable vehicle, incorporates various steering system schemes, for example, steer-by-wire and driver interface steering. These steering system schemes typically include a steering column to translate steering input into output, which works in conjunction with a steering linkage to ultimately cause the vehicle's wheels (or other elements) to turn the vehicle. Some steering columns are axially adjustable between positions to provide flexibility in steering wheel position and to allow for more comfortable driving positions for drivers of different sizes or for autonomous driving capabilities. Many axially adjustable steering columns also include tilt actuators that allow for tilting motion around one or more pivot points.

[0003] In addition to providing adjustability, axially adjustable steering column assemblies can also include a collapse function, providing safety benefits during an energy absorption event. A locking mechanism may be required to hold a moving section of the steering column assembly in a desired position after axial adjustment. One type of locking mechanism commonly used in the automotive industry is known as a telescopic positive locking mechanism. When designing a telescopic positive locking mechanism, care is typically taken to allow proper locked and unlocked states of the steering column. The unlocked state must ensure that the full telescopic / axial adjustment range is available.When the steering column assembly is locked, it must maintain a fixed telescopic / axial position under normal vehicle operating conditions. However, during a folding event, various measures can be implemented to ensure a required folded state and / or range of movement within a given area of ​​applied load.

[0004] US patent 2021 / 0403074A1 discloses an axially adjustable steering column according to the preamble of claim 1.

[0005] US 2019 / 0100242A1 teaches an axially adjustable steering column comprising: a first sleeve and a second sleeve, wherein the first sleeve is axially adjustable relative to the second sleeve; an adjusting lever and a locking mechanism, wherein the adjusting lever selectively moves the locking mechanism between a locked position and an unlocked position, wherein the locked position prevents axial adjustment of the first sleeve relative to the second sleeve in both axial directions and the unlocked position allows adjustment of the first sleeve relative to the second sleeve.The locking mechanism comprises two energy-absorbing straps, a first of which defines a first row of axially extending teeth and a second row of axially extending teeth. The first row of teeth and the second row of teeth are arranged on respective faces of the energy-absorbing strap that are oriented perpendicular to each other. A cam with a plurality of teeth is provided, which, in the locked position, can be engaged with the first row of teeth and, in the unlocked position, are disengaged from the first row of teeth. The cam is rotatably mounted on a pin to allow the plurality of teeth of the cam to rotate in and out of engagement with the first row of teeth of the energy-absorbing strap.A second row of teeth on the second of the absorbing belts can be engaged in the locked position with the second row of teeth of the first energy-absorbing belt, e.g. via a pyrotechnic device, and is released from the first row of teeth in the unlocked position.

[0006] From US patent 2020 / 0398885A1, an axially adjustable steering column is known, comprising: a first sleeve and a second sleeve, wherein the first sleeve is axially adjustable relative to the second sleeve; an adjusting lever and a first locking mechanism, wherein the adjusting lever selectively moves the first locking mechanism between a locked position and an unlocked position, the locked position preventing axial adjustment of the first sleeve relative to the second sleeve in both axial directions and the unlocked position allowing adjustment of the first sleeve relative to the second sleeve. An energy-absorbing belt is provided, defining a first row of teeth extending axially and a second row of teeth extending axially and parallel thereto in the same plane. Locking teeth of a second locking mechanism can be adjusted by linear displacement, e.g.,The teeth are engaged via a pyrotechnic device or solenoid and released from the second row of teeth in the unlocked position. Depending on the severity of an impact event, one or both rows of teeth are used for energy absorption.

[0007] The object of the present invention is to improve the reliability of a locking mechanism of an axially adjustable steering column.

[0008] This problem is solved by an axially adjustable steering column with the features of claim 1.

[0009] Advantageous embodiments are specified in the dependent claims. SUMMARY

[0010] According to one aspect of the disclosure, an axially adjustable steering column comprises a first sleeve. The steering column also comprises a second sleeve, wherein the first sleeve is axially adjustable relative to the second sleeve. The steering column further comprises an adjusting lever. The steering column also further comprises a locking mechanism, wherein the adjusting lever selectively moves the locking mechanism between a locked position and an unlocked position, the locked position preventing axial adjustment of the first sleeve relative to the second sleeve in both axial directions, and the unlocked position allowing adjustment of the first sleeve relative to the second sleeve. The locking mechanism comprises an energy-absorbing belt defining a first row of axially extending teeth and a second row of axially extending teeth.The locking mechanism also includes a first cam with a plurality of teeth that can be engaged with the first row of teeth in the locked position and released from the first row of teeth in the unlocked position. The locking mechanism further includes a second cam with a plurality of teeth that can be engaged with the second row of teeth in the locked position and released from the second row of teeth in the unlocked position.

[0011] According to another aspect of the disclosure, an axially adjustable steering column comprises a first sleeve. The steering column also comprises a second sleeve, wherein the first sleeve is axially adjustable relative to the second sleeve. The steering column further comprises an adjusting lever. The steering column further comprises a locking mechanism, wherein the adjusting lever selectively moves the locking mechanism between a locked position and an unlocked position, the locked position preventing axial adjustment of the first sleeve relative to the second sleeve in both axial directions, and the unlocked position allowing adjustment of the first sleeve relative to the second sleeve.

[0012] These and other aspects of the present disclosure are disclosed in the following detailed description of the embodiments, the attached claims and the attached figures. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The disclosure is best understood from the following detailed description, when read in conjunction with the accompanying drawings. It is emphasized that, in accordance with usual practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features have been arbitrarily enlarged or reduced for the sake of clarity. Fig. Figure 1 schematically represents a steering system that includes an adjustable steering column assembly; Fig. Figure 2 is a perspective view of a section of the adjustable steering column assembly, illustrating a locking mechanism; Fig. Figure 3 is a perspective view of a first cam element of the locking mechanism; Fig. Figure 4 is a perspective view of a second cam element of the locking mechanism; Fig. Figure 5 is a first perspective view of the locking mechanism in a locked position; Fig. Figure 6 is a second perspective view of the locking mechanism in the locked position, with a lower mantle removed for illustrative purposes; Fig. Figure 7 is a first perspective view of the locking mechanism in an unlocked position; Fig. Figure 8 is a second perspective view of the locking mechanism in the unlocked position, with the lower mantle removed for illustrative purposes; Fig. Figure 9 is a perspective view of a first cam and a second cam of the locking mechanism in the locked position; Fig. Figure 10 is a perspective view of the first cam and the second cam of the locking mechanism in the unlocked position; Fig. Figure 11 is a perspective view of the locking mechanism in the locked position; and Fig. Figure 12 is a perspective view of the locking mechanism in the unlocked position. DETAILED DESCRIPTION

[0014] The following discussion is directed at various embodiments of the disclosure. The disclosed embodiments should not be interpreted or otherwise used as limiting the scope of the disclosure, including the claims. Furthermore, a person skilled in the art will understand that the following description has broad application and that the discussion of any particular embodiment is intended only as an example of that embodiment and not as limiting the scope of the disclosure, including the claims, to that embodiment.

[0015] Now, with reference to the drawings in which the various embodiments herein are shown and described, without limiting them, the figures illustrate embodiments of a steering column assembly that is axially adjustable and includes a locking mechanism with improved reliability and other operational advantages. The axial adjustability can result from a relative movement between two or more sleeves, allowing axial movement between them. For example, a first sleeve and a second sleeve move in a relative telescopic, sliding, or translational configuration.

[0016] Initially referring to Fig. Figure 1 illustrates a steering system 40 for a vehicle according to the principles of this disclosure in general terms. The vehicle can be any suitable vehicle, such as a car, truck, SUV, minivan, crossover, any other passenger vehicle, any suitable commercial vehicle, or any other suitable vehicle. Furthermore, the principles of this disclosure can be applied to other vehicles, such as airplanes, boats, trains, drones, or other vehicles.

[0017] The steering system 40 can be configured as a driver interface steering system, an autonomous driving system, or a system that enables both a driver interface and autonomous steering. The steering system can include an input device 42, such as a steering wheel, whereby a driver can mechanically provide steering input by turning the steering wheel. An airbag device 43 can be located on or near the input device 42. A steering column assembly 44 extends along an axis from the input device 42 to an output assembly 46. The output assembly 46 can include a pinion shaft assembly, an I-shaft, a universal joint, steer-by-wire components, or any other features conventionally arranged opposite the input device 42.The steering column assembly 44 can comprise at least two axially adjustable parts, for example, a first sleeve 48 and a second sleeve 50, which are axially adjustable relative to each other. The first sleeve 48 and the second sleeve 50 can alternatively be configured as supports, rails, or other elements that allow axial movement between them. The axial movement can include sliding, telescopic, translational, and other axial movements. The steering column assembly 44 can include a support 51 that connects the steering column at least partially to the vehicle 10. An adjustable lever 52 can be operatively connected to the first sleeve 48, the second sleeve 50, or the support 51 to allow axial or tilt adjustment of the steering column assembly 44. In some embodiments, the behavior of the adjustable lever 52 can be controlled by a control system 300, which includes a CPU unit.In some embodiments, the behavior of the adjustable lever 52 can be controlled manually.

[0018] The steering column assembly 44 is movable over a range of positions from an extended position to a retracted position. Although the second sleeve 50 is considered to be axially adjustable, the first sleeve 48 is axially adjustable relative to the second sleeve 50 to define, at least partially, the extended and retracted positions of the steering column assembly 44. For example, the first sleeve 48 can be referred to as the "upper sleeve" and the second sleeve 50 can be referred to as the "lower sleeve".

[0019] A 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 autonomous and driver interface steering systems. The steering gear assembly 54 can then be connected to a drive axle 58 via an output shaft 60. The output shaft 60 can include a steering column lever and a sector gear or other conventional components. The output shaft 60 is operatively connected to the steering gear assembly 54 such that a rotation of the steering gear input shaft 56 causes a reaction movement of the output shaft 60, causing the drive axle to turn the wheels 22. In other embodiments, the steering column assembly 44 is not directly mechanically connected to the steering gear assembly 54.Such a design can be described as a steer-by-wire system.

[0020] Fig. Figure 2 illustrates a general section of the adjustable steering column assembly 44 with a bidirectional locking mechanism 62. The adjustable lever 52 is operatively coupled to the bidirectional locking mechanism 62, but is not illustrated for the sake of clarity of the locking mechanism 62. The lever 52 includes a section that is in contact with the locking mechanism 62 to selectively switch the locking mechanism 62 between a locked position ( Fig. 5, Fig. 6, Fig. 9 and Fig. 11) and an unlocked position ( Fig. 7, Fig. 8, Fig. 10 and Fig. 12) to move as described herein.

[0021] Now, with reference to Fig. 2-4 The locking mechanism 62 comprises an energy-absorbing strap 64, a first cam 66, and a second cam 67. In some embodiments, the first cam 66 and the second cam 67 are made of identical materials, while other embodiments use different materials. The choice of material can enable different locking forces to be achieved. Regardless of the materials, in a locked position of the locking mechanism 62 ( Fig. 5, Fig. 6, Fig. 9 and Fig. 11) The first cam 67 and the second cam 67 engage with the energy-absorbing belt 64. The engagement between the cams 66, 67 and the energy-absorbing belt 64 occurs with tooth-to-tooth contact, as illustrated and described herein. In an unlocked position of the locking mechanism 62 ( Fig. 7, Fig. 8, Fig. 10 and Fig. 12) the cams 66, 67 are spaced apart from the energy-absorbing belt 64 to ensure release.

[0022] With reference to Fig. 5 and Fig. Section 6 defines the energy-absorbing belt 64 as comprising a first row of teeth 80 and a second row of teeth 82. The first row of teeth 80 forms a first axially extending path of teeth on the energy-absorbing belt 64. The second row of teeth 82 forms a second axially extending path of teeth on the energy-absorbing belt 64. The term "axially extending" refers to a direction that is essentially parallel to the longitudinal axis of the steering column assembly 44. The teeth of the first row of teeth 80 are oriented at an angle that differs from the orientation angle of the second row of teeth 82. The first row of teeth is arranged on a first surface of the energy-absorbing belt 64, and the second row of teeth is arranged on a second surface (i.e., different from the first surface) of the energy-absorbing belt 64.According to the invention, the first surface and the second surface are essentially oriented perpendicular to each other.

[0023] Now, with reference to Fig. 3- Fig. The first cam 66 defines a first set of teeth 84 that meshes with the first row of teeth 80 in the locked position. Similarly, the second cam 67 defines a second set of teeth 86 that meshes with the second row of teeth 82 in the locked position. Since the first row of teeth 80 and the second row of teeth 82 are oriented at different angles, the engagement of the first set of teeth 84 of the first cam 66 and the first row of teeth 80 of the energy-absorbing belt 64 provides a locking mechanism in a first axial direction of the steering column assembly 44, while the engagement of the second set of teeth 86 of the second cam 67 and the second row of teeth 82 of the energy-absorbing belt 64 provides a locking mechanism in a second axial direction of the steering column assembly 44, which is opposite to the first axial direction.In other words, one of the cams 66 or 67 resists movement in a "telescoping direction" of the first sleeve 48, while the other cam 66 or 67 resists movement in an "out-telescoping direction" of the first sleeve 48. Therefore, the locking mechanism 62 is referred to as a bidirectional locking mechanism that uses separate paths of teeth.

[0024] With reference to Fig. 5-12, the lever 52 or an intermediate component, during operation, contacts the first cam 66 and rotates the first cam 66 to disengage the first set of teeth 84 of the first cam 66 from the first row of teeth 80 of the energy-absorbing belt 80 when the adjustable lever 52 is rotated from a locked position (i.e., the steering column assembly 44 cannot be adjusted) to an unlocked position (i.e., the steering column assembly 44 can be adjusted). During the rotation of the first cam 66 toward the unlocked position, a first cam surface 90 of the first cam 66 rotates relative to a second cam surface 92 of the second cam 67.In particular, the first cam 66 is rotatably mounted on a pin to allow the teeth 84 of the first cam 66 to rotate in and out of engagement with the first row of teeth 80 of the energy-absorbing belt 64, while the second cam 67 is mounted on the pin to allow the teeth 86 of the second cam 67 to slide in and out of engagement with the second row of teeth 82 of the energy-absorbing belt 64. The second cam 67 slides along the pin, bolt, or the like 94—around which the first cam 66 rotates—to disengage the second set of teeth 86 from the second row of teeth 82. Thus, the adjustable lever 52 does not couple directly with the energy-absorbing belt 64, but instead locks and unlocks the steering column assembly 44 with the cams 66 and 67.In the unlocked position, movement of the steering column assembly 44 is possible, whereby the upper sleeve 48 can be movable relative to the lower sleeve 50.

[0025] With reference to Fig.Figures 5-8, 11, and 12 describe a preload element 120, such as a torsion spring, which preloads the cams 66 and 67 by rotating them toward the locked position of the locking mechanism 62. Specifically, the preload element 120 comprises a first spring leg 122 in contact with the first cam 66 to preload the first cam 66 into the locked position and consequently the second cam 67 into the locked position. The preload force is selected to prevent movement into the unlocked position until such force is overcome by movement of the lever 52. Although a torsion spring is given as an example of the preload element 120, it is understood that any suitable component that preloads the cams 66 and 67 toward the locked position can be used.

Claims

[1] Axially adjustable steering column, comprising: a first coat (48); a second jacket (50), wherein the first jacket (48) is axially adjustable relative to the second jacket (50); an adjusting lever (52); a locking mechanism (62), wherein the adjusting lever (52) selectively moves the locking mechanism (62) between a locked position and an unlocked position, wherein the locked position prevents axial adjustment of the first shell (48) relative to the second shell (50) in both axial directions and the unlocked position allows adjustment of the first shell (48) relative to the second shell (50), wherein the locking mechanism (62) comprises: an energy-absorbing belt (64) defining a first row of teeth (80) extending axially; a first cam (66) with a plurality of teeth (84) which, in the locked position, can be engaged with the first row of teeth (80) and, in the unlocked position, are disengaged from the first row of teeth (80), wherein the first cam (66) is rotatably mounted on a pin to allow the plurality of teeth (84) of the first cam (66) to rotate in and out of engagement with the first row of teeth (80) of the energy-absorbing belt (64); and a second cam (67) with a plurality of teeth (86), wherein the second cam (67) is mounted on a pin (94), characterized by , that the energy-absorbing belt (64) defines a second row of teeth (82) extending axially, the first row of teeth (80) and the second row of teeth (82) are arranged on respective surfaces of the energy-absorbing belt (64) which are oriented perpendicular to each other, the multitude of teeth (86) of the second cam (67) can be engaged with the second row of teeth (82) in the locked position and are released from the second row of teeth (82) in the unlocked position, and the second cam (67) is mounted on the pin (94) to allow the multitude of teeth (86) of the second cam (67) to move in and out of engagement with the second row of teeth (82) of the energy-absorbing belt (64). [2] Axially adjustable steering column according to claim 1, wherein the first row of teeth (80) and the second row of teeth (82) are angled differently from each other. [3] Axially adjustable steering column according to claim 1, wherein the first cam (66) is pre-tensioned in the direction of the locked position by a pre-tensioning element (120) in contact with the first cam (66) in a rotating manner. [4] Axially adjustable steering column according to claim 3, wherein the preload element (120) is a torsion spring. [5] Axially adjustable steering column according to claim 1, wherein the first cam (66) and the second cam (67) are formed from the same materials. [6] Axially adjustable steering column according to claim 1, wherein the first cam (66) and the second cam (67) are formed from different materials. [7] Axially adjustable steering column according to claim 1, wherein the first cam (66) comprises a first cam surface (90) in contact with a second cam surface (92) of the second cam (67), wherein a rotational movement of the first cam (66) in the direction of the unlocked position displaces the second cam (67).

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