Dual telescoping locking mechanism for manually adjustable steering column assembly

Abstract

The present disclosure relates to a dual telescoping locking mechanism for a manually adjustable steering column assembly. An axially adjustable steering column includes a first shroud and a second shroud, wherein the first shroud is axially adjustable relative to the second shroud. The steering column further includes an adjustment lever and an adjustment bolt operatively coupled to the adjustment lever. The steering column further includes a locking mechanism, wherein the adjustment lever selectively moves the locking mechanism between a locked position and an unlocked position, wherein the locked position prevents axial adjustment of the first shroud relative to the second shroud in both axial directions and the unlocked position allows adjustment of the first shroud relative to the second shroud, the locking mechanism including a plurality of cams operatively coupled to the adjustment bolt, wherein the plurality of cams rotate simultaneously to selectively engage and disengage a tooth of each of the plurality of cams with a tooth of a stationary object formed in or coupled to the second shroud.

Description

Technical Field

[0001] The following description relates to vehicle steering systems, and more specifically to locking mechanisms for such steering systems. Background Technology

[0002] Vehicles (such as cars, trucks, SUVs, crossovers, minivans, boats, aircraft, all-terrain vehicles, recreational vehicles, or other suitable vehicles) include a variety of steering system schemes (e.g., steer-by-wire and driver-interface steering). These steering system schemes typically include a steering column for translating steering inputs into outputs that interact with steering linkages to ultimately cause the vehicle's wheels (or other elements) to turn. Some steering columns are axially adjustable between positions to provide flexibility in steering wheel positioning and to facilitate a more comfortable driving posture for drivers of different body types or to enhance autonomous driving capabilities. Many axially adjustable steering columns also include a rake actuator that allows tilting movement about one or more pivot points.

[0003] A locking mechanism may be required to hold the movable portion of the steering column assembly in the desired position after axial adjustment. One type of locking mechanism commonly used in the automotive industry is called a telescopic forward locking mechanism. When designing a telescopic forward locking mechanism, it is generally important to allow for proper column locking and unlocking states. The unlocked state must ensure that the full range of telescopic / axial adjustment is allowed. Under normal vehicle operating conditions, when the steering column assembly is locked, it must maintain a fixed telescopic / axial position. However, vehicle manufacturers (i.e., OEMs) more frequently reduce the leverage required by the operator and increase the telescopic holding force requirements in the locked state. Therefore, meeting OEM requirements makes frictional retention between the steering column bushings (which often depends on the locking condition) increasingly challenging.

[0004] Therefore, it is necessary to continuously improve the operating framework of the locking mechanism to improve packaging, load requirements and reliability. Summary of the Invention

[0005] According to one aspect of this disclosure, an axially adjustable steering column includes a first sleeve and a second sleeve, wherein the first sleeve is axially adjustable relative to the second sleeve. The steering column also includes an adjusting rod and a locking mechanism, wherein the adjusting rod 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 two axial directions, and the unlocked position allows adjustment of the first sleeve relative to the second sleeve. The locking mechanism includes a first toothed plate defining an axially extending first series of teeth, wherein the first toothed plate is disposed on a first side of the second sleeve. The locking mechanism also includes a second toothed plate defining an axially extending second series of teeth, wherein the second toothed plate is disposed on a second side of the second sleeve. The locking mechanism further includes a first cam having a plurality of teeth that are capable of engaging with the first series of teeth in the locked position and disengaging from the first series of teeth in the unlocked position. The locking mechanism further includes a second cam having multiple teeth that engage with the second series of teeth in the locked position and disengage from the second series of teeth in the unlocked position.

[0006] According to another aspect of this disclosure, an axially adjustable steering column includes a first sleeve and a second sleeve, wherein the first sleeve is axially adjustable relative to the second sleeve. The steering column also includes an adjusting rod and an adjusting bolt operatively coupled to the adjusting rod. The steering column further includes a locking mechanism, wherein the adjusting rod 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 two axial directions, and the unlocked position allows adjustment of the first sleeve relative to the second sleeve. The locking mechanism includes a plurality of cams operatively coupled to the adjusting bolt, wherein the plurality of cams rotate simultaneously such that the teeth of each of the plurality of cams selectively engage and disengage with the teeth of a stationary object forming or coupled to the second sleeve.

[0007] These and other aspects of this disclosure are disclosed in the following detailed description of embodiments, the appended claims, and the accompanying drawings. Attached Figure Description

[0008] This disclosure is best understood in conjunction with the accompanying drawings, based on the following description. It should be emphasized that, in accordance with conventional practice, the various features in the drawings are not necessarily drawn to scale. Instead, for clarity, the dimensions of the various features have been arbitrarily enlarged or reduced.

[0009] Figure 1 A steering system including an adjustable steering column assembly is schematically depicted.

[0010] Figure 2AThis is a perspective view of a portion of the adjustable steering column assembly, illustrating the first side of the locking mechanism with the locking mechanism in the locked position.

[0011] Figure 2B This is a perspective view of a portion of the adjustable steering column assembly, illustrating the second side of the locking mechanism with the locking mechanism in the locked position.

[0012] Figure 3A This is a perspective view of the first side of the locking mechanism with the locking mechanism in the unlocked position.

[0013] Figure 3B This is a perspective view of the second side of the locking mechanism with the locking mechanism in the unlocked position.

[0014] Figure 4 This is the first embodiment of a cam for a locking mechanism.

[0015] Figure 5 This is a second embodiment of the cam in the locking mechanism.

[0016] Figure 6 This is a front view of the locking mechanism, illustrating... Figure 4 or Figure 5 The connection between the rod bolt and the cam. Detailed Implementation

[0017] The following discussion pertains to various embodiments of this disclosure. The disclosed embodiments should not be construed as or otherwise intended to limit the scope of this disclosure (including the claims). Furthermore, those skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is merely illustrative and not intended to imply that the scope of this disclosure (including the claims) is limited to that embodiment.

[0018] Referring now to the accompanying drawings, in which various embodiments are shown and described herein, but not limited thereto, these figures illustrate embodiments of a steering column assembly that is axially adjustable and includes a locking mechanism that provides improved reliability and other operational benefits. Axial adjustability can be caused by relative movement between two or more sleeves that allow axial movement therebetween. For example, a first sleeve and a second sleeve may move in a relative telescopic, sliding, or translational configuration.

[0019] First refer to Figure 1The present disclosure generally illustrates a steering system 40 for a vehicle. The vehicle may include 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 aircraft, ships, trains, drones, or other vehicles.

[0020] The steering system 40 can be configured as a driver-interface steering system, an automatic driving system, or a system that allows both driver-interface and automatic steering. The steering system may include an input device 42 (such as a steering wheel) through which a driver mechanically provides steering input by turning the steering wheel. An airbag device 43 may be located on or near the input device 42. A steering column assembly 44 extends axially from the input device 42 to an output assembly 46. The output assembly 46 may include a pinion shaft assembly, an I-shaft, a cardan joint, a steer-by-wire component, or any other feature conventionally positioned relative to the input device 42. The steering column assembly 44 may include at least two axially adjustable portions, for example, a first sleeve 48 and a second sleeve 50 axially adjustable relative to each other. Alternatively, the first sleeve 48 and the second sleeve 50 may be configured as brackets, rails, or other components that allow axial movement between them. Axial movement may include sliding, telescoping, translation, and other axial movements. The steering column assembly 44 may include a bracket 51 that at least partially connects the steering column to the vehicle 10. The adjustable lever 52 can be operatively connected to one of the first sleeve 48, the second sleeve 50, or the bracket 51 to facilitate axial or tilt adjustment of the steering column assembly 44 by selectively switching the steering column assembly 44 between a locked and unlocked state. In some embodiments, the behavior of the adjustable lever 52 can be controlled via a control system 300 including a CPU unit. In some embodiments, the behavior of the adjustable lever 52 can be controlled manually.

[0021] The steering column assembly 44 is movable within a position range from an extended position to a retracted position. While the second sleeve 50 is envisioned to be axially adjustable, the first sleeve 48 is axially adjustable relative to the second sleeve 50 to at least partially define the extended and retracted positions of the steering column assembly 44. For example, the first sleeve 48 may be referred to as the "upper sleeve," and the second sleeve 50 may be referred to as the "lower sleeve."

[0022] Steering gear assembly 54 can be connected to output assembly 46 via steering gear input shaft 56. Steering gear assembly 54 can be configured as a rack and pinion steering gear, a recirculating ball steering gear, or any other type of steering gear associated with automatic steering systems and driver interface steering systems. Steering gear assembly 54 can then be connected to drive wheel axle 58 via output shaft 60. Output shaft 60 may include a steering rocker arm and sector gears or other conventional components. Output shaft 60 is operatively connected to steering gear assembly 54 such that rotation of steering gear input shaft 56 causes responsive movement of output shaft 60 and causes drive wheel axle to rotate wheel 22. In other embodiments, steering column assembly 44 is not directly mechanically connected to steering gear assembly 54. Such embodiments may be referred to as steer-by-wire systems.

[0023] Figure 2A , Figure 2B , Figure 3A and Figure 3B A portion of an adjustable steering column assembly 44 having a two-way locking mechanism 100 is generally illustrated. An adjustable lever 52 is operatively coupled to the two-way locking mechanism 100, but is not illustrated for clarity of the locking mechanism 100. As described herein, lever 52 includes contact with the locking mechanism 100 to selectively position the locking mechanism 100 in a locked position (…). Figure 2A and Figure 2B ) and unlock location ( Figure 3A and Figure 3B The part that moves between ).

[0024] The locking mechanism 100 includes an adjusting bolt 102 that extends substantially transversely to the axial direction of the steering column assembly 44 (e.g., across the vehicle direction). An adjusting rod 52 is operatively coupled to the adjusting bolt 102 on a first side 104 of the steering column assembly 44, as shown below. Figure 2A and Figure 3A As shown. The first side 104 may be referred to as the "pole side" of the steering column assembly 44 and the locking mechanism 100. The adjusting bolt 102 extends through the steering column assembly 44 to protrude through the second side 106 of the steering column assembly 44, as shown. Figure 2B and Figure 3B As shown. The second side 106 may be referred to as the "thrust bearing side" of the steering column assembly 44 and the locking mechanism 100. In some embodiments, the adjusting bolt 102 is partially disposed within the sleeve 103, which serves as a damper for surrounding components.

[0025] The locking mechanism 100 includes an adjusting rod 52, an adjusting bolt 102, a first cam 110, a first toothed plate 112, a second cam 114, and a second toothed plate 116. The first cam 110 and the first toothed plate 112 are located on a first side of the locking mechanism 100 (i.e., the first side of the steering column assembly 44), which is the rod side of the steering column assembly 44. Figure 2A and Figure 3A As shown. The second cam 114 and the second toothed plate 116 are located on the second side of the locking mechanism 100 (i.e., the second side of the steering column assembly 44), which is the side of the steering column assembly 44 opposite to the rod side, as shown. Figure 2B and Figure 3B As shown.

[0026] In addition to extending through the first toothed plate 112 and the second toothed plate 116 and the steering column itself as described above, the adjusting bolt 102 also extends through the first cam 110 and the second cam 114. Figure 6 As shown, a portion of the adjusting bolt 102 is formed with a non-circular cross-section 120, which substantially corresponds to the inner wall 122 of the cams 110 and 114. The portion of the adjusting bolt 102 with the non-circular cross-section 120 contacts the inner wall 122 of the cams 110 and 114, or has a small gap between them. Therefore, rotation of the adjusting bolt 102 caused by rotation of the adjusting rod 52 results in rotation of the first cam 110 and the second cam 114. A first biasing member 130 (such as a coil spring, torsion spring, or any other suitable alternative) tilts the first cam 110 towards... Figure 2A and Figure 2B The locking mechanism 100 is rotatably biased in its locked position. Similarly, the second biasing member 132 (such as a coil spring, torsion spring, or any other suitable alternative) tilts the second cam 114 toward... Figure 2A and Figure 2B The locking position of the locking mechanism 100 is rotatably biased. The aforementioned rotation of the adjusting bolt 102 overcomes the spring force, causing the first cam 110 and the second cam 114 to rotate away from the locking position. Figure 3A and Figure 3B The unlock location.

[0027] The first toothed plate 112 and the second toothed plate 116 may have any suitable outer peripheral geometry for a particular application. In the illustrated, non-limiting example, the toothed plates 112, 116 are generally rectangular to be seated within recesses defined by the respective sidewalls of the steering column. The toothed plates 112, 116 may be mechanically fastened to be positioned within the steering column sidewalls, or may be press-fitted or welded therein. Any other suitable coupling techniques are within the scope of this disclosure. As shown, some embodiments of one or both of the toothed plates 112, 116 include a protrusion 140 extending from the outer wall 142 of the toothed plates 112, 116 to be received within a recess 144 defined by the sidewalls of the steering column (see Figure 144). Figure 2A The opposite configuration may exist, in which the outer wall 142 of the tooth plates 112, 116 defines a recess, and the steering column sidewall includes a protrusion to engage within the recess. In either configuration, the protrusion-recess arrangement provides assembly error-proofing features to ensure that the first tooth plate 112 and the second tooth plate 116 are assembled to the sidewall of the steering column assembly 44 in the correct orientation so that the teeth described herein are correctly positioned for operation.

[0028] The inner wall 146 of the first toothed plate 112 includes a first series of teeth 150 along a portion of the inner wall 146. In the illustrated embodiment, the first series of teeth 150 of the first toothed plate 112 is formed along the upper portion of the inner wall 146. The inner wall 148 of the second toothed plate 116 includes a second series of teeth 152 along a portion of the inner wall 148. In the illustrated embodiment, the second series of teeth 152 of the second toothed plate 116 is formed along the lower portion of the inner wall 148. The first series of teeth 150 forms a first axially extending tooth track. The second series of teeth 152 forms a second axially extending tooth track. The term "axially extending" refers to a direction substantially parallel to the longitudinal axis of the steering column assembly 44.

[0029] A first cam 110 defines a first set of teeth 160 that engages with a first series of teeth 150 in a locked position. Similarly, a second cam 114 defines a second set of teeth 162 that engages with a second series of teeth 152 in a locked position. Because the first series of teeth 150 and the second series of teeth 152 are oriented at different angles when properly mounted within the column sidewall, the engagement of the first set of teeth 160 of the first cam 110 with the first series of teeth 150 of the first toothed plate 112 provides locking in a first axial direction of the steering column assembly 44, while the engagement of the second set of teeth 162 of the second cam 114 with the second series of teeth 152 of the second toothed plate 116 provides locking in a second axial direction of the steering column assembly 44 opposite to the first axial direction. In other words, one of the cams 110 and 114 resists the movement of the first sleeve 48 in the "telescope-in" direction, while the other of the cams 110 and 114 resists the movement of the first sleeve 48 in the "telescope-out" direction. Therefore, the locking mechanism 100 is referred to as a bidirectional locking mechanism utilizing separate toothed tracks.

[0030] In operation, when the adjustable lever 52 is rotated from the locked position (i.e., the steering column assembly 44 cannot be adjusted) to the unlocked position (i.e., the steering column assembly 44 can be adjusted), the lever 52 or the intermediate component causes the adjusting bolt 102 to rotate, thereby rotating the first cam 110 and the second cam 114. The rotation of the first cam 110 disengages the first set of teeth 160 of the first cam 110 from the first series of teeth 150 of the first toothed plate 112. Similarly, the rotation of the second cam 114 disengages the second set of teeth 162 of the second cam 114 from the second series of teeth 152 of the second toothed plate 116. As described above, the first biasing member 130 rotatably biases the first cam 110 to maintain the first set of teeth 160 locked engagement with the first series of teeth 150 of the first toothed plate 112, and the second biasing member 132 rotatably biases the second cam 114 to maintain the second set of teeth 162 locked engagement with the second series of teeth 152 of the second toothed plate 116. However, the manual rotation of the adjustable lever 52 and thus the manual rotation of the adjusting bolt 102 overcomes the biasing force of the biasing members 130, 132, so that the gear sets 160, 162 disengage from the first series of teeth 150 and the second series of teeth 152, respectively, thereby moving the locking mechanism 100 to the unlocked position.

[0031] It should be understood that the first toothed plate 112 and the second toothed plate 116 utilize a common toothed plate design while still providing locking in opposite directions during the operation described herein. This is achieved by changing the orientation of the teeth 150, 152 during assembly to meet the requirement of providing locking in both axial directions (e.g., retracted and extended). The protrusion and notch arrangement disclosed herein ensures that the toothed plates 112, 116 are properly assembled to provide dual locking functionality. Similarly, the first cam 110 and the second cam 114 utilize a common cam design while still providing locking in opposite directions during operation. The cams 110, 114 are assembled to the adjusting bolt 102 in corresponding positions, which allows the cams 110, 114 to rotate simultaneously to achieve engagement and disengagement of the teeth, thereby achieving locking and unlocking functions. Therefore, the toothed plates 112, 116 and the cams 110, 114 are claimed to have the same geometry and shape, serving as identical components.

[0032] Figure 4 Examples Figure 2A , Figure 2B , Figure 3A , Figure 3B and Figure 6 The cam design depicted in the illustration. In the illustrated embodiment, bias feature 130, teeth 160, and non-circular inner wall 122 are shown. Figure 5 An example of a stamped embodiment of the cam disclosed herein is illustrated and is generally designated by the numeral 200. The stamped cam 200 also includes teeth 260 and a non-circular inner wall 222 to contact the adjusting bolt 102 and facilitate rotation with it. An offset feature is formed as part of the stamped component as one or more spring-like segments 230 of the cam 200. Therefore, when used throughout the locking mechanism 100, cams 110, 114, and 200 share a common function.

[0033] The above embodiments, implementations, and aspects have been described to allow for an easy understanding of this disclosure and are not intended to limit it. Rather, this disclosure is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, and its scope should be interpreted in the broadest possible sense to cover all such modifications and equivalent structures permitted under the law.

Claims

1. An axially adjustable steering column, the axially adjustable steering column comprising: First sheath; The second sheath, wherein the first sheath is axially adjustable relative to the second sheath; Adjusting lever; and A locking mechanism, wherein the adjusting rod selectively moves the locking mechanism between a locked position and an unlocked position, wherein the locked position prevents axial adjustment of the first sheath relative to the second sheath in two axial directions, and the unlocked position allows adjustment of the first sheath relative to the second sheath, wherein the locking mechanism includes: A first toothed plate defines a first series of teeth extending axially, wherein the first toothed plate is disposed on a first side of the second sheath; The second toothed plate defines a second series of teeth extending axially, wherein the second toothed plate is disposed on a second side of the second sheath; A first cam, the first cam having a plurality of teeth, the plurality of teeth of the first cam being capable of engaging with a first series of teeth in the locked position and disengaging from the first series of teeth in the unlocked position; and A second cam has a plurality of teeth that are capable of engaging with a second series of teeth in the locked position and disengaging from the second series of teeth in the unlocked position.

2. The axially adjustable steering column according to claim 1, wherein, The first cam and the second cam rotate simultaneously.

3. The axially adjustable steering column according to claim 1, wherein, The axially adjustable steering column further includes an adjusting bolt operatively connected to the adjusting rod, wherein the adjusting bolt extends through the second sheath and operatively connects to the first cam and the second cam.

4. The axially adjustable steering column according to claim 3, wherein, During the rotation of the adjusting bolt, the first cam and the second cam rotate simultaneously.

5. The axially adjustable steering column according to claim 1, wherein, The inner wall of each of the first cam and the second cam has a non-circular cross-section corresponding to the non-circular cross-section of the adjusting bolt at the contact area.

6. The axially adjustable steering column according to claim 1, wherein, The first toothed plate and the second toothed plate are the same component.

7. The axially adjustable steering column according to claim 1, wherein, When the first series of teeth of the first toothed plate are assembled to the second sheath, they are positioned on the upper section of the inner wall of the first toothed plate, and when the second series of teeth of the second toothed plate are assembled to the second sheath, they are positioned on the lower section of the inner wall of the second toothed plate.

8. The axially adjustable steering column according to claim 1, wherein, In the assembled state, the first toothed plate is disposed within a recess defined by a first sidewall of the second sheath, wherein, in the assembled state, the second toothed plate is disposed within a recess defined by a second sidewall of the second sheath.

9. The axially adjustable steering column according to claim 1, wherein, The first series of teeth and the second series of teeth are angled in opposite directions when assembled into the second sheath.

10. The axially adjustable steering column according to claim 1, wherein, The first cam and the second cam are each rotatably biased toward the locked position by a first biasing member and a second biasing member, respectively.

11. The axially adjustable steering column according to claim 10, wherein, At least one of the first biasing member and the second biasing member is a helical spring.

12. An axially adjustable steering column, the axially adjustable steering column comprising: First sheath; The second sheath, wherein the first sheath is axially adjustable relative to the second sheath; Adjusting lever; An adjusting bolt, operatively connected to the adjusting rod; and A locking mechanism, wherein the adjusting rod selectively moves the locking mechanism between a locked position and an unlocked position, wherein the locked position prevents axial adjustment of the first sheath relative to the second sheath in two axial directions, and the unlocked position allows adjustment of the first sheath relative to the second sheath, the locking mechanism including a plurality of cams operatively coupled to the adjusting bolt, wherein the plurality of cams rotate simultaneously to selectively engage and disengage a tooth of each of the plurality of cams with a tooth of a stationary object forming or coupled to the second sheath.

13. The axially adjustable steering column according to claim 12, wherein, The inner wall of each of the first cam and the second cam has a non-circular cross-section corresponding to the non-circular cross-section of the adjusting bolt at the contact area.

14. The axially adjustable steering column according to claim 12, wherein, The plurality of cams includes a first cam and a second cam, and the axially adjustable steering column further includes: A first toothed plate defines a first series of axially extending teeth, wherein the first toothed plate is disposed on a first side of the second sheath, wherein the first cam includes a plurality of teeth, the plurality of teeth of the first cam being capable of engaging with the first series of teeth in the locked position and disengaging from the first series of teeth in the unlocked position; and A second toothed plate defines a second series of teeth extending axially, wherein the second toothed plate is disposed on a second side of the second sheath, wherein the second cam includes a plurality of teeth, the plurality of teeth of the second cam being capable of engaging with the second series of teeth in the locked position and disengaging from the second series of teeth in the unlocked position.

15. The axially adjustable steering column according to claim 14, wherein, The first toothed plate and the second toothed plate are the same component.

16. The axially adjustable steering column according to claim 14, wherein, When the first series of teeth of the first toothed plate are assembled to the second sheath, they are positioned on the upper section of the inner wall of the first toothed plate, and when the second series of teeth of the second toothed plate are assembled to the second sheath, they are positioned on the lower section of the inner wall of the second toothed plate.

17. The axially adjustable steering column according to claim 14, wherein, In the assembled state, the first toothed plate is disposed within a recess defined by a first sidewall of the second sheath, wherein, in the assembled state, the second toothed plate is disposed within a recess defined by a second sidewall of the second sheath.

18. The axially adjustable steering column according to claim 14, wherein, The first series of teeth and the second series of teeth are angled in opposite directions when assembled into the second sheath.

19. The axially adjustable steering column according to claim 12, wherein, The first cam and the second cam are each rotatably biased toward the locked position by a first biasing member and a second biasing member, respectively.

20. The axially adjustable steering column according to claim 19, wherein, At least one of the first biasing member and the second biasing member is a helical spring.

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