SPRING BUMPER ASSEMBLY FOR AN ADJUSTABLE STEERING COLUMN
A steering column with an energy absorbing assembly. The steering column comprising a first jacket and a second jacket that is axially movable with respect to the first jacket. The second jacket includes a window. The energy absorbing apparatus includes a lock cam located in the window and connected to the second jacket and a strap body that is connected to the first jacket. The lock cam includes a toothed portion for selective engagement with the strap body. The energy absorbing apparatus includes at least one of a cam spring located between the lock cam and an edge of the window or a bumper.
The following description relates to energy absorbing devices, and more particularly, to a cam spring and a bumper for a lock cam in an adjustable steering column.
BACKGROUNDA 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 assembly for translating steering input to an output that interacts with a steering linkage to ultimately cause the vehicle wheels to turn. Steering columns include various safety features, such as airbags to lessen impact forces. In addition, many steering column assemblies are collapsible and include one or more energy absorption features, such as energy absorbing straps, that allow a certain amount of controlled compression.
Some energy absorbing straps are configured to roll along their length to absorb energy, and are often referred to as roll straps. Typically, roll straps absorb energy during the deformation of the strap in an impact event wherein kinetic energy can be dissipated through compression of the steering column assembly. These energy absorbing straps include a series of teeth that become intermeshed with a strap actuator. The strap actuators typically include a locking cam or other device that is moveable between engagement and disengagement with the series of teeth. The energy absorbing strap is typically located in a long channel extending through a lower jacket and is retained therein with a complicated series of non-integral stiffening brackets and guides. The strap actuator is then connected to one of the stiffening brackets and the locking cam is biased with a small and complicated wire-form cam spring. The long channel in the lower jacket allows for strap travel, which requires added material to compensate for lost rigidity and strength. Space also oftentimes has to be made for a tail of the strap to feed out unimpeded to control the absorption load further creating packaging difficulties.
Accordingly, there is a continuing need to improve the operational framework of energy absorption features to improve upon packaging, load requirements, and tuneabiltiy.
SUMMARYThe foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent embodiments do not depart from the spirit and scope of the invention as set forth in the appended claims. This section provides a general summary of the disclosure and is not to be interpreted as a complete and comprehensive listing of all of the objects, aspects, features and advantages associated with the present disclosure.
An aspect of the disclosure includes an energy absorbing assembly. The energy absorbing assembly comprises a lock cam including a toothed portion, a bumper having at least one loop, and a pivot pin connected to the lock cam and extending through the at least one loop.
Another aspect of the disclosure includes an energy absorbing assembly. The energy absorbing assembly comprises a lock cam including a tail portion and a toothed portion, a cam spring operably connected to the lock cam, and a pivot pin connected to the lock cam and the lock cam biased by the cam spring in a pivot direction.
Another aspect of the disclosure includes a steering column with an energy absorbing assembly. The steering column comprising a first jacket and a second jacket that is axially movable with respect to the first jacket. The second jacket includes a window. The energy absorbing apparatus includes a lock cam located in the window and connected to the second jacket and a strap body that is connected to the first jacket. The lock cam includes a toothed portion for selective engagement with the strap body. The energy absorbing apparatus includes at least one of a cam spring located between the lock cam and an edge of the window or a bumper.
These and other aspects of the present disclosure are disclosed in the following detailed description of the embodiments, the appended claims, and the accompanying figures.
The disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to-scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.
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 assembly for translating steering input to an output that interacts with a steering linkage to ultimately cause the vehicle wheels to turn. Steering columns include various safety features, such as airbags to lessen impact forces. In addition, many steering column assemblies are collapsible and include one or more energy absorption features, such as energy absorbing straps, that allow a certain amount of compression.
Referring initially to
In some embodiments, the vehicle 20 may further include a steering system 40. The steering system 40 may 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 device 42, such as a steering wheel, wherein a driver may mechanically provide a steering input by turning the steering wheel. A steering column assembly 44 may include a steering column 45 that extends along an axis 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, steer-by-wire components or any other features conventionally located opposite the input device 42.
The steering column 45 may include at least two axially adjustable portions, for example, a first jacket 48 and a second jacket 50 that are axially adjustable with respect to one another. The first jacket 48 may be an upper jacket and a second jacket 50 may be a lower jacket, wherein the first jacket 48 and the second jacket 50 are permitted to move axially with respect to one another during an impact or other compressive forces. The axial movement may include sliding, telescopic, translating, and other axial movements. The steering column assembly 44 may include additional portions that permit axial movement and brackets that provide rake and tilt movement. More particularly, the steering column assembly 44 may include a powered actuator (not shown) wherein the axial adjustments are machine driven.
An energy absorbing assembly 52 may be located on one or each of the first jacket 48, the second jacket 50, any brackets, or combinations thereof, and provide at least one of variable stroke load absorption settings and a steering column lock functionality. The energy absorbing assembly may dissipate kinetic energy between the first jacket 48 and the second jacket 50.
A steering gear assembly 54 may connect to the output assembly 46 via a steering gear input shaft 56. The steering gear assembly 54 may 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 assembly 54 may then connect to a driving axle 58 via an output shaft 60. The output shaft 60 may include a pitman arm and sector gear or other traditional components. The output shaft 60 is operably connected to the steering gear assembly 54 such that a rotation of the steering gear input shaft 56 causes a responsive movement of the output shaft 60 and causes the drive axle to turn the wheels 61.
With continued reference to
With reference now to
The first flat portion 96 includes a series of teeth 100 extending therefrom. A pair of sidewalls 102 may extend along the first portion 96 on opposite sides of the teeth 100. Each sidewall 102 may extend between a lower stop tab 104 and an upper stop tab 106. In use, the lower stop tab 104 may contact a portion of the energy absorbing actuator 66 and create a hard stop in a first direction and the upper stop tab 106 may contact a portion of the energy absorbing actuator 66 and create a hard stop in a second direction. More particularly, the lock cam 68 includes a bumper 108. The bumper 108 includes a pair of loops 110 spaced from a bridge portion 112. The lock cam 68 includes a bumper slot 114 for retaining the bridge portion 112 and the loops 110 are located on opposite surface of the lock cam 68 and the pivot pin 80 extends through each loop 110. Each of the loops 110 are sized and spaced to contact the lower stop tab 104 and the upper stop tab 106 in the hard stop positions. The second jacket 50 may further define a channel 111 sized to guide the lower stop tab 104 and the upper stop tab 106 in a direction along the axis A.
With reference to
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.
Claims
1. (canceled)
2. The energy absorbing assembly of claim 3, wherein the at least one loop includes a pair of loops on opposite sides of the lock cam.
3. An energy absorbing assembly for a steering column comprising:
- a lock cam including a toothed portion;
- a bumper having at least one loop; and
- a pivot pin connected to the lock cam and extending through the at least one loop, wherein the lock cam includes a bumper slot and the bumper includes a bridge portion extending into the bumper slot.
4. The energy absorbing assembly of claim 3, wherein the bumper slot is defined by at least one prong having a hook portion.
5. The energy absorbing assembly of claim 3, wherein bridge portion includes at least one rib in locked engagement with the hook.
6. (canceled)
7. (canceled)
8. An energy absorbing assembly for a steering column comprising:
- a lock cam including a tail portion and a toothed portion;
- a cam spring operably connected to the tail portion; and
- a pivot pin connected to the lock cam and the lock cam biased by the cam spring in a pivot direction, wherein the cam spring includes a first leg extending along the tail portion and a second leg spaced from the first leg by a bend, wherein the first leg extends from a first clip at a transverse angle therefrom for contacting a provided jacket of a steering column.
9. The energy absorbing assembly of claim 8, wherein the second leg extends from a second clip at a transverse angle therefrom for contacting the provided jacket.
10. The energy absorbing assembly of claim 9, wherein the cam spring includes a retaining tab for connecting to the provided jacket.
11. The energy absorbing assembly of claim 8, wherein the first clip includes a clip bend for spacing an edge on a terminal end of the first clip from the provided jacket.
12. An energy absorbing assembly for a steering column comprising:
- a lock cam including a tail portion and a toothed portion;
- a cam spring operably connected to the tail portion; and
- a pivot pin connected to the lock cam and the lock cam biased by the cam spring in a pivot direction, wherein the cam spring includes a housing extending to at least one pin interface surface.
13. The energy absorbing assembly of claim 12, wherein the pivot pin includes at least one groove and the at least one pin interface surface extends into the at least one groove.
14. The energy absorbing assembly of claim 12, wherein the at least one pin interface surface includes a pair of interface surfaces and the at least one groove includes a pair of grooves.
15. A steering column comprising:
- a first jacket and a second jacket that is axially movable with respect to the first jacket;
- the second jacket including a window;
- an energy absorbing apparatus including a lock cam located in the window and connected to the second jacket and a strap body that is connected to the first jacket;
- the lock cam including a toothed portion for selective engagement with the strap body; and
- at least one of a cam spring located between the lock cam and an edge of the window or a bumper, wherein the strap body includes a lower stop tab and an upper stop tab and wherein the energy absorbing apparatus includes the bumper that contacts the lower stop tab and the upper stop tab.
16. (canceled)
17. The steering column of claim 15, wherein the bumper includes a pair of loops on opposite surfaces of the lock cam and a pivot pin is connected to the lock cam and extends through the pair of loops.
18. The steering column of claim 17, wherein the bumper includes a bridge portion spacing the loops and the lock cam includes a bumper slot that the bridge portion is located in.
19. The energy absorbing assembly of claim 15, wherein the energy absorbing apparatus includes the cam spring and the cam spring includes a first leg extending along the lock cam and a second leg spaced from the first leg by a bend and extending along an edge of the window.
20. The energy absorbing assembly of claim 19, wherein the cam spring includes a pair of spring retaining tabs and the second jacket includes a groove connected to the retaining tabs.
Type: Application
Filed: Dec 17, 2021
Publication Date: Jun 22, 2023
Inventors: Melvin L. Tinnin (Clio, MI), Joen C. Bodtker (Flint, MI)
Application Number: 17/555,203