STEERING COLUMN ARRANGEMENT WITH TEAR LINE

Abstract

Steering column assembly (10) comprising: a lower shell; an upper shell which is at least partially incorporated into the lower shell; a shell wall (22) formed integrally with the lower shell, wherein the shell wall (22) extends longitudinally from a first end (50) to a second end (52) and has a first side (53) and a second side (51);and an energy absorption band (24) which is offset to the first side (53) of the shell wall (22) to form a recess extending along the shell wall (22), wherein the energy absorption band (24) has a first end (54) and a second end (56), wherein the energy absorption band (24) has at least one tear line (58) at an interface with the shell wall (22), characterized in that the steering column assembly (10) further comprises a dart feature (150) which forms several projections (152) of the energy absorption band (24), wherein at least one of the projections (152) is arranged individually along a lateral plane and along a central axis (88) of the energy absorption band (24).

Description

Currently, many steering column assemblies are equipped with kinetic energy absorption devices to reduce the effects of an impact event. There are several different types and variations of these kinetic energy absorption devices, typically related to metal deformation. Many of the methods available today use a separate energy absorbing assembly attached to the steering column assembly.The publication DE 195 03 124 A1 discloses a steering column arrangement according to the preamble of claim 1. Similar steering column arrangements are known, for example, from the publications DE 10 2014 104 354 B3 and US 2006 / 02 901 28 A1.SUMMARYIt is an object of the invention to provide a steering column assembly that can better reduce the effects of an impact event.This object is achieved according to the invention by the features of the independent claims. Advantageous further developments are defined in the dependent claims.BRIEF DESCRIPTION OF THE DRAWINGSThe subject matter considered to be the present disclosure is specifically disclosed and separately claimed in the claims at the end of the specification. The foregoing and other features and advantages of the present disclosure will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: FIG. 1 is an illustration of a steering column assembly; FIG. 2 shows the lower part of the steering column arrangement with a lower jacket arrangement with a jacket wall; FIG. 3 shows the lower part of the steering column arrangement with a jacket wall; FIG. 4 is a partial view of the shroud wall with an integrally formed energy absorbing band shown in a first end view; FIG. 5 is a side cross-sectional view of the shroud wall with an energy absorbing band of constant thickness formed thereon; FIG. 6 is a front sectional view of the skirt wall with an integrally formed energy absorption band with constant overlap; FIG. 7 is a side cross-sectional view of the shroud wall with a variable overlap energy absorbing band formed thereon; FIG. 8 is a plan view of the shroud wall with a variable thickness energy absorbing band formed thereon; FIG. 9 is a front sectional view of the shroud wall with an integrally formed energy absorbing band of variable cross-sectional thickness; FIG. 10 is a plan view of the wall of the jacket with an energy absorption band formed thereon in a wave-shaped configuration; FIG. 11 is a plan view of the skirt wall with an integrally formed energy absorption band which is tapered in width; FIG. 12 is a top view of the shroud wall with an integrally formed variable width energy absorbing band of hourglass configuration; FIG. 13 is a top view of the shroud wall with an integrally formed variable width energy absorbing band of inverted hourglass configuration; FIG. 14 is a side sectional view of the shroud wall with an integrally formed energy absorbing band having a curved, increasing overlap; FIG. 15 is a side view of the shroud wall with an integrally formed energy absorbing band having a linearly increasing overlap; FIG. 16 is a side sectional view of the shroud wall with an integrally formed energy absorption band having curvilinear waveform overlap; FIG. 17 is a side sectional view of the shroud wall with an integrally formed energy absorbing band having a segmental waveform overlap; FIG. 18 is a side sectional view of the shroud wall with an integrally formed energy absorbing band in an embodiment with undulating increasing overlap; FIG. 19 is a side view of the shroud wall with an integrally formed energy absorbing band having a wave-shaped decreasing overlap; FIG. 20 is front and top views of the molded energy absorbing band having a suture feature not in accordance with the present invention and having a single long protrusion; FIG. 21 is front and top views of the molded energy absorption band having an approximation feature having a plurality of protrusions along a central axis of the upper shell; FIG. 22 is front and top views of the suturing feature having a plurality of protrusions; FIG. 23 is an illustration of a skirt wall with an integrally formed energy absorbing band having a standard slit after tearing; FIG. 24 is a front and top view of the shroud wall with an integrally formed energy absorbing band of single slot configuration; FIG. 25 is a front and top view of the shroud wall with an integrally formed energy absorbing band in flanged slot configuration; FIG. 26 is a front and top view of the shroud wall with an integrally formed energy absorbing band of conical slot configuration; FIG. 27 is a top view of the shroud wall with an integrally formed hourglass slot energy absorbing band; and FIG. 28 is a top view of the shroud wall with an integrally formed energy absorbing band of inverted hourglass slot configuration.DETAILED DESCRIPTIONReferring now to the figures, in which the present disclosure is described with reference to certain embodiments, without limiting the same, it is to be understood that the disclosed embodiments are merely an illustration of the present disclosure that may be embodied in various and alternative forms. Various elements of the disclosed embodiments may be combined or omitted to form further embodiments of the present disclosure. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present disclosure.Referring now to FIGS. 1-3, a steering column assembly 10 is illustrated. The steering column assembly 10 extends along a steering column axis 12. The steering column assembly 10 is configured as a non-telescopic steering column assembly, but at least a portion of the steering column assembly 10 is axially slidable along the steering column axis 12 for a folding motion for energy absorption. However, it should be appreciated that the embodiments disclosed herein may be applied to a telescopically adjustable column. A telescopically adjustable embodiment includes a locking device for selectively engaging and disengaging the integrated energy absorption band described herein. The steering column assembly 10 includes a lower shroud assembly 14, an upper shroud assembly 16, a mounting bracket 18, an rake lever 20, a shroud wall 22, and an energy absorbing band 24.The lower shell assembly 14 is connected to a vehicle structure (not shown) by the mounting bracket 18. The lower shell assembly 14 defines an opening 28 that at least partially receives the upper shell assembly 16. The upper shroud assembly 16 is slidable along the steering column axis 12 when a load on impact exceeds the design threshold. The adjustment lever 20 is configured such that the inclination angle relative to the mounting bracket 18 can be adjusted about the pivot axis.The adjustment lever 20 is pivotably connected to the lower jacket assembly 14 and / or the upper jacket assembly 16 and / or the mounting bracket 18. In at least one embodiment, adjustment lever 20 is pivotally connected to lower shell assembly 14, upper shell assembly 16, and mounting bracket 18 by a fastener 30 that passes through lower shell assembly 14, upper shell assembly 16, and mounting bracket 18, respectively.The adjustment lever 20 is pivotable or movable between first and second positions by the operator of the vehicle. The adjustment lever 20 is pivotable or movable between the first position and the second position about a substantially transverse arcuate path 32 of the lever that extends transversely to the steering column axis 12. The first position of the adjustment lever 20 corresponds to a position in which the upper jacket assembly 16 is prevented from moving or adjusting the inclination relative to the mounting bracket 18 about the pivot axis. The first position maintains the entire shroud assembly 14, 16, and thus a steering wheel, when connected thereto, in a drive-stable position. The second position of the adjustment lever 20 corresponds to a position in which movement or inclination adjustment of the combined jacket arrangement 14, 16 relative to the mounting bracket 18 about the pivot axis is permitted.The lower shell assembly 14 includes a lower portion, referred to herein as a shell wall 22, an upper portion 42, and two side walls 44. The skirt wall 22 also includes a pair of side portions 48 that extend longitudinally from a first end 50 to a second end 52 of the skirt wall 22. The shroud wall 22 also has a first side 53 facing inward toward the upper shroud assembly and a second side 51 facing outward away from the upper shroud assembly (FIG. 4 ). The energy absorbing tape 24 is located on the skirt 22 between the side portions 48 of the skirt 22 of the lower shell assembly 14. the energy absorbing tape 24 has a first end 54 and a second end 56 and at least one tear line 58 at an intersection with the skirt 22.Referring to FIGS. 2-4, the energy absorbing band 24 has at its first end 54 a loop assembly 60 that engages the opening 46 of the upper jacket assembly 16. The energy absorption band 24 also has an offset 62 with respect to the jacket wall 22. The offset is located on the first side 51 of the skirt wall 22, and the offset 62 creates the tear lines 58 on both sides where the energy absorption band 24 joins the skirt wall 22. A reduced wall 64 in the energy absorption band 24 also creates a stress riser [stress riser] at which tearing will begin. The depth of the offset 62 may be adjusted to achieve the desired amount of dissipated energy.In FIGS. 5-7, various configuration possibilities for the energy absorption band 24 are illustrated. An energy absorption band thickness 80 and a shell wall thickness 82 is constant from the first end 54 to the second end 56 of the energy absorption band 24 in some embodiments (see FIGS. 5 and 6 ). As used herein, the term "thickness" refers to the overlap that provides the stress energy for the cracking portion of the EA mechanism. This fraction is added to the stress energy provided by the bend radius and thickness 82 of the offset portion designated 24.The energy absorption band 24 may also have a variable thickness 80 from the first end 54 to the second end 56 (see FIG. 7 ). The thickness 80 of the energy absorbing band 24 is determined by the amount of offset 62 between the energy absorbing band 24 and the shell wall 22. Tear lines 58 are shown on both sides of energy absorbing tape 24 where energy absorbing tape 24 joins sheath wall 22.According to FIGS. 8 and 9, a jacket wall 22 with an integrally formed energy absorption band 24 is shown. The energy absorption band 24 may have a constant width 84 with a variable amount of offset 62, and a tip 86 on a central axis 88 of the energy absorption band 24 (see FIG. 9 ). The offset 62 is smaller in a region closer to the intersection of the energy absorption band 24 and the shell wall 22, and gradually increases in height as it approaches the central axis 88 of the energy absorption band 24.Referring to Figs. 10-13, various shapes of the energy absorbing band 24 of the skirt wall 22 are illustrated. The energy absorption band 24 may have a wavy pattern 100 with both curvilinear 102 and sawtoothed edges 104, the pattern having a minimum width 106 and a maximum width 108 with a constant and repeating pattern. The minimum width 106 is less than the maximum width 108 (see FIG. 10 ). The energy absorption band 24 may have a conical pattern 120 having a maximum width 108 at the first end 54 and a minimum width 106 at the second end 56, or a minimum width 106 at the first end 54 and a maximum width 108 at the second end 56 (see FIG. 11 ). The energy absorption band 24 may have an hourglass pattern 130, each with a line segment 132 at the first end 54 and the second end 56, each line segment 132 merging into a curvilinear segment 134. The line segments 132 are wider than the curvilinear segment 134 (see FIG. 12 ) in some embodiments. The energy absorption band 24 may have an inverted hourglass pattern 136 with a line segment 132 at the first end 54 and the second end 56, each line segment 132 merging into a curvilinear segment 134. The line segments 132 are narrower than the curvilinear segment 134 (see FIG. 13 ).Further embodiments for variants of the energy absorption band 24 of the jacket wall 22 are illustrated in FIGS. 14-19. The energy absorption band 24 may have an increasing height 140 (this "height 140" is also analogous to the "thickness 80" previously referred to as "overlap"), with the height 140 being greater at the first end 54 of the energy absorption band 24 compared to the second end 56. The increasing height 140 may be a curved increase, with the change in height 140 beginning more at the first end 54 of the energy absorption band 24 and then decreasing as the second end 56 approaches (see FIG. 14 ). The increasing height 140 may be a linear increase when the change in height from the first end 54 of the energy absorption band 24 to the second end 56 of the energy absorption band 24 occurs at a constant rate (see FIG. 15 ). The energy absorption band 24 may have a height 140 that increases and decreases in a curvilinear waveform 142 (see FIG. 16 ) or in a segmental waveform 144 (see FIG. 17 ). The energy absorption band 24 may have a pattern with an overall increase in height 140 from the first end 54 of the energy absorption band 24 to the second end 56 of the energy absorption band 24 (see FIG. 18 ). The energy absorption band 24 may have a pattern in which the overall height 140 decreases from the first end 54 of the energy absorption band 24 to the second end 56 of the energy absorption band 24 (see FIG. 19 ).In Figs. 20-22, an approximation feature 150 is shown within the energy absorption band 24 of the skirt wall 22. The approximation feature 150 is a protrusion 152 of the energy absorption band 24. the approximation feature 150 in the energy absorption band 24 increases the moment of inertia, i.e., more energy is needed to cause the energy absorption band 24 to roll. The protrusion 152 may vary in length and profile height as desired. The protrusion 152 may be formed in the same operation as that in which the energy absorption band 24 is formed.The approach feature 150 is formed as a single long protrusion 152 (see FIG. 20 ) in an embodiment not according to the invention. The single long protrusion 152 is located in the energy absorption band central axis 88.The approach feature 150 of the present invention is comprised of a plurality of protrusions 152. According to one embodiment, each protrusion 152 lies individually in a lateral plane and is located on the central axis 88 of the energy absorption band 24 (see FIG. 21 ). A configuration is also possible in which some of the protrusions 152 are juxtaposed along a lateral plane parallel to each other and are each offset in the opposite direction to the central axis 88, and some of the protrusions 152 are individually disposed along a lateral plane and directly on the central axis 88 of the energy absorption band 24 (see FIG. 22 ). The approximation feature 150 may also be a combination of the above features to improve the tunability.In Figs. 23-28, a slit 160 is shown in the energy absorption band 24 of the skirt wall 22. The slits 160 may vary in size and shape to change the energy absorption rate of the band along with changes in the energy absorption bandwidth 84 configured to meet the energy absorption requirements. The bending radius is determined by the mounting space of the upper shell assembly 16 and the lower shell assembly 14 and varies due to the applied load and any external constraint that limits its growth. However, the slit width controls the amount of material to be deformed that affects the energy level. The slot 160 may be an elongated slot 162, i.e., the energy absorption band 24 has a single elongated slot 162 along the central axis 88 of the energy absorption band 24. The elongated slot 162 is located at a substantially equal distance from both sides where the energy absorption band 24 joins the skirt wall 22 (see FIGS. 23 and 24 ).The slot 160 may be a curled slot 164 (see FIG. 25 ) having a flat edge 166 around the curled slot 164 itself, with the curled slot 164 located on the central axis 88 of the energy absorption band 24. The slot 160 may be a conical slot 168 (see FIG. 26 ), wherein the conical slot 168 is located along the central axis 88 of the energy absorption band 24. The conical slot 168 may be narrower at the first end 54 of the energy absorbing band 24 and become wider as it approaches the second end 56 of the energy absorbing band 24. The tapered slot 168 may also be wider at the first end 54 of the energy absorption band 24 and narrow as the second end 58 of the energy absorption band 24 is approached. The slot 160 may be in the form of an hourglass slot 170 (see FIG. 27 ). The hourglass slot 170 is located along the central axis 88 of the energy absorption band 24, and the hourglass slot 170 has a line segment 172 at each of the first end 54 and the second end 56 of the energy absorption band 24. Each line segment 172 meets in a curvilinear segment 174, and the line segments 172 are wider than the curvilinear segment 174. The slot 160 may be an inverted hourglass slot 176 (see FIG. 28 ). The inverted hourglass slot 176 is located along the central axis 88 of the energy absorption band 24, and the inverted hourglass slot 176 has a line segment 172 at each of the first end 54 and the second end 56 of the energy absorption band 24. Each line segment 172 meets in a curvilinear segment 174, and the line segments 172 are narrower than the curvilinear segment 174.In this specification, the terms "attach," "mount," "connected," "coupled," "couple," "mount," or "mount" are to be construed to mean that a component or element is connected, in any manner, to or contacts, or is integrally formed with another element, either directly or indirectly via at least one intermediate component.

Claims

A steering column assembly (10) comprising: a lower shroud; an upper shroud at least partially received within the lower shroud; a shroud wall (22) integrally formed with the lower shroud, the shroud wall (22) extending longitudinally from a first end (50) to a second end (52) and having a first side (53) and a second side (51); and an energy absorbing band (24) offset to the first side (53) of the shroud wall (22) to form a recess extending along the shroud wall (22), the energy absorbing band (24) having a first end (54) and a second end (56), the energy absorbing band (24) having at least one tear line (58) at an intersection with the shroud wall (22), characterized in that the steering column assembly (10) further comprises an approach feature (150) forming a plurality of protrusions (152) of the energy absorbing band (24), at least one of the protrusions (152) being individually disposed along a lateral plane and along a central axis (88) of the energy absorbing band (24).The steering column assembly (10) of claim 1, wherein the shroud wall (22) is disposed within an opening (46) defined by the upper shroud to operatively connect the lower shroud to the upper shroud.The steering column assembly (10) of claim 2, wherein the upper shell opening (46) has a hook feature that engages a loop feature (60) of the first end (54) of the energy absorption band (24).The steering column assembly (10) of claim 1, wherein the energy absorption band (24) has a thickness (80) that is not constant from the first end (54) to the second end (56) of the energy absorption band (24).The steering column assembly (10) of claim 1, wherein the energy absorbing band (24) produces a stress increase at which tearing along the at least one tear line (58) of the energy absorbing band (24) will begin.The steering column assembly (10) of claim 1, wherein the energy absorption band (24) has a thickness (80) that is constant from the first end (54) to the second end (56) of the energy absorption band (24).Steering column assembly (10) according to Claim 1, in which the energy absorption band (24) is formed integrally with the casing wall (22).The steering column assembly (10) of claim 1, wherein the energy absorption band (24) has a wavy pattern (100) with either curvilinear (102) or sawtooth-shaped edges (104), the pattern (100) having a minimum width (106) and a maximum width (108) with a constant and repeating pattern, the minimum width (106) being less than the maximum width (108).The steering column assembly (10) of claim 1, wherein the energy absorption band (24) has a conical pattern (120) having a maximum width (108) at the first end (54) and a minimum width (106) at the second end (56).The steering column assembly (10) of claim 1, wherein the energy absorption band (24) has a conical pattern (120) with a minimum width (106) at the first end (54) and a maximum width (108) at the second end (56).The steering column assembly (10) of claim 1, wherein the energy absorption band (24) comprises one of an hourglass pattern (130) having a line segment (132) and a curvilinear segment (134).The steering column assembly (10) of claim 1, wherein the energy absorption band comprises one of an inverted hourglass pattern (136) having a line segment (132) and a curvilinear segment (134).A steering column assembly (10) comprising: a lower shroud assembly (14); an upper shroud assembly (16) at least partially received within the lower shroud assembly (14); a shroud wall (22) integrally formed with the lower shroud, the shroud wall (22) extending from a first end (50) to a second end (52) and having a first side (53) and a second side (51), the shroud wall (22) comprising a pair of lateral portions extending longitudinally from the first end (50) to the second end (52); and an energy absorbing band (24) formed integrally with the shroud wall (22) and disposed between the lateral portions of the shroud wall (22), wherein an intersection of the energy absorbing band (24) and the lateral portions of the shroud wall (22) forms a pair of tear lines (58), the energy absorbing band (24) having a central axis (88) disposed equidistant from each intersection with the shroud wall (22), characterized in that the steering column assembly (10) further comprises a suturing feature (150) forming a plurality of protrusions (152) of the energy absorbing band (24), wherein at least one of the protrusions (152) is individually disposed along a lateral plane and along the central axis (88) of the energy absorbing band (24).The steering column assembly (10) of claim 13, wherein at least two of the protrusions (152) are adjacent to each other along a lateral plane parallel to each other and offset from the central axis (88) in an opposite direction to each other.A steering column assembly (10) comprising: a lower shroud assembly (14); an upper shroud assembly (16) at least partially received within the lower shroud assembly (14); a shroud wall (22) integrally formed with the lower shroud assembly (14), the shroud wall (22) extending from a first end (50) to a second end (52) and having a first side (53) and a second side (51), the shroud wall (22) comprising a pair of lateral portions extending longitudinally from the first end (50) to the second end (52); an energy absorbing band (24) formed integrally with the shroud wall (22) and disposed between the lateral portions of the shroud wall (22), wherein an intersection of the energy absorbing band (24) and the lateral portions forms a pair of tear lines (58), the energy absorbing band (24) having a central axis (88) disposed equidistant from each intersection with the shroud wall (22); and a slot feature (160) having an opening on the energy absorbing band (24), characterized in that the steering column assembly (10) further comprises an approximation feature (150) forming a plurality of protrusions (152) of the energy absorbing band (24), wherein at least one of the protrusions (152) is individually disposed along a lateral plane and along the central axis (88) of the energy absorbing band (24).The steering column assembly (10) of claim 15, wherein the slot feature (160) is a curled slot (164).The steering column assembly (10) of claim 15, wherein the slot feature (160) is a conical slot (168).The steering column assembly (10) of claim 15, wherein the slot feature (160) is an hourglass slot (170) and / or an inverted hourglass slot (176).

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