AU2012216535A1 - Support structure including a unidirectional crumple zone - Google Patents

Abstract

Abstract A support structure (100) enables, on a vehicle with a side step (105), side impact crash forces to be transferred to a vehicle chassis (110) in a manner similar to a vehicle without a side step. The support structure 5 (100) includes a frame (107) having an attachment end (120) and a distal end (125). A compression axis (130) extends between the attachment end (120) and the distal end (125). A transverse axis (135) is substantially orthogonal to the compression axis (130). A unidirectional crumple zone (140) is attached to the frame (107) between the attachment end (120) 10 and the distal end (125), and defines a crumple zone face (127) substantially orthogonal to the compression axis (130). An anvil member, such as a spacer block (150), covers only a portion of the crumple zone face (127) and has an edge substantially parallel to the crumple zone face (127). LfLP coc IIn

Description

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "SUPPORT STRUCTURE INCLUDING A UNIDIRECTIONAL CRUMPLE ZONE" The following statement is a full description of this invention, including the best method of performing it known to me/us: 1 TITLE SUPPORT STRUCTURE INCLUDING A UNIDIRECTIONAL CRUMPLE ZONE 5 FIELD OF THE INVENTION The present invention relates to vehicle safety. In particular, although not exclusively, the invention relates to a support structure for a vehicle side step. 10 BACKGROUND TO THE INVENTION Automotive engineers have significantly increased the safety of vehicles through the effective use of various devices that absorb and dissipate energy during a crash. Such devices include crumple zones and air bags. 15 Crumple zones are typically designed into vehicle structures and include geometric features that localize deformation, such as thinner cross sections or depressions/indentations in the structures. Other methods incorporate different materials with better crush performance into a vehicle structure to form a "crush box", which provides a desired energy 20 dissipation function. Generally a crumple zone is a volume that absorbs at least a portion of the energy of a collision and lengthens the duration of the collision event. By increasing a duration of a collision event, and by absorbing a portion of the collision energy, crumple zones can substantially reduce crash G forces experienced by vehicle occupants. 25 Air bags enable a controlled deceleration of a vehicle occupant, while other elements of a vehicle structure, such as crumple zones, absorb and dissipate crash energy. Most design and engineering developments regarding crumple zones and air bags have been directed to front impact collisions. 30 However, more recent improvements in side impact safety include, for example, the widespread use of side airbags and improved side impact chassis structural engineering.

2 However, it is well known that both original equipment manufacturer (OEM) and aftermarket "bolt-on" vehicle components, such as "bull bars", winches, tow bars and side steps, can alter where energy is absorbed and dissipated in a vehicle during a crash. 5 There is therefore a need for an improved support structure for attaching components to vehicles. OBJECTS OF THE INVENTION An object of the present invention is to overcome or alleviate one or 10 more limitations of the prior art, including providing an improved support structure for attaching components to vehicles. SUMMARY OF THE INVENTION According to one aspect, the present invention is a support 15 structure, including: a frame having an attachment end and a distal end, a compression axis extending from the attachment end to the distal end, and a transverse axis substantially orthogonal to the compression axis; a unidirectional crumple zone, attached to the frame between the 20 attachment end and the distal end, defining a crumple zone face substantially orthogonal to the compression axis; and an anvil member covering only a portion of the crumple zone face and having an edge substantially parallel to the crumple zone face; wherein the unidirectional crumple zone is oriented to a) deform 25 under a compressive force applied at the distal end toward the attachment end along the compression axis by folding a portion of the crumple zone face over the edge of the anvil member, and b) resist deformation under a transverse force applied at the distal end along the transverse axis. Preferably, the unidirectional crumple zone includes deformation 30 members.

3 Preferably, at least one of the deformation members is placed in compression under the compressive force and is placed in tension under the transverse force. Preferably, the unidirectional crumple zone includes a truss 5 structure. Preferably, the support structure is a side step of a vehicle. Preferably, the attachment end is attached to a frame or chassis of a vehicle. Preferably, the anvil member comprises a spacer block that is 10 attached to a frame or chassis of a vehicle. Preferably, the unidirectional crumple zone is oriented to resist deformation under a transverse force applied at the distal end in either direction along the transverse axis. Preferably, the attachment end includes a clamping plate. 15 Preferably, the attachment end is adjacent to the unidirectional crumple zone. Preferably, a second crumple zone is attached to the distal end of the frame. Preferably, the second crumple zone includes a tubular element. 20 Preferably, elements of the unidirectional crumple zone move relative to the attachment end along both the compression axis and the transverse axis during deformation of the unidirectional crumple zone under the compressive force. Preferably, the crumple zone is tuned to match side impact energy 25 absorbing qualities of a vehicle body. Preferably, the frame includes bent sheet steel. Preferably, a central web section including at least a part of the unidirectional crumple zone is attached to the frame. Preferably, the portion of the crumple zone face folds over the edge 30 of the anvil member by approximately 90 degrees.

4 BRIEF DESCRIPTION OF THE DRAWINGS To assist in understanding the invention and to enable a person skilled in the art to put the invention into practical effect, preferred embodiments of the invention are described below by way of example only 5 with reference to the accompanying drawings, in which: FIG. 1 is a diagram illustrating a front view of a support structure for a side step of a vehicle, according to an embodiment of the present invention; FIGs. 2A, 2B, 2C, 2D, 2E and 2F are a series of computer 10 generated images illustrating a front view of the sequential deformation of the support structure of FIG. 1 during a side impact; FIG. 3 is a front view of a support structure, according to an alternative embodiment of the present invention; FIG. 4 is a front view of a support structure, according to another 15 alternative embodiment of the present invention; FIG. 5 is a front view of a support structure, according to another alternative embodiment of the present invention; FIG. 6 is a front view of a support structure, according to another alternative embodiment of the present invention; 20 FIG. 7 is a front view of a support structure, according to another alternative embodiment of the present invention; FIG. 8 is a front view of a support structure, according to another alternative embodiment of the present invention; FIG. 9 is a front perspective view that further illustrates the support 25 structure of FIG. 1. Those skilled in the art will appreciate that minor deviations from the layout of components as illustrated in the drawings will not detract from the proper functioning of the disclosed embodiments of the present invention. 30 5 DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention include a support structure for a side step of a vehicle. Elements of the invention are illustrated in concise outline form in the drawings, showing only those specific details 5 that are necessary to understanding the embodiments of the present invention, but so as not to clutter the disclosure with excessive detail that will be obvious to those of ordinary skill in the art in light, of the present description. In this patent specification, adjectives such as first and second, left 10 and right, upper and lower, top and bottom, transverse, etc., are used solely to define one element or method step from another element or method step without necessarily requiring a specific relative position or sequence that is described by the adjectives. Words such as "comprises" or "includes" are not used to define an exclusive set of elements or 15 method steps. Rather, such words merely define a minimum set of elements or method steps included in a particular embodiment of the present invention. Referring to FIG. 1, a diagram illustrates a front view of a support structure 100 for a side step 105 of a vehicle, according to an embodiment 20 of the present invention. As shown, the support structure 100 is attached to a chassis 110 of the vehicle, generally between the front and rear wheels, and extends away from a side of the vehicle just below a body structure 115 of the vehicle. As is well known according to conventional side steps of the prior art, a vehicle driver or passenger can then step up 25 onto the side step 105 when climbing into or out of the vehicle. The support structure 100 includes a frame 107 having an attachment end 120 and a distal end 125. A compression axis 130 extends between the attachment end 120 and the distal end 125. A transverse axis 135 is substantially orthogonal to the compression axis 30 130. A unidirectional crumple zone 140 is attached to the frame 107 between the attachment end 120 and the distal end 125, and defines a crumple zone face 127 substantially orthogonal to the compression axis 6 130. An anvil member, such as a spacer block 150, covers only a portion of the crumple zone face 127 and has an edge substantially parallel to the crumple zone face 127. The unidirectional crumple zone 140 is oriented to a) deform under 5 a compressive force applied at the distal end 125 toward the attachment end 120 along the compression axis 130 by folding a portion of the crumple zone face 127 over the edge of the anvil member, and b) resist deformation under a transverse force applied at the distal end 125 along the transverse axis 135. According to some embodiments, the spacer 10 block 150 thus functions as an anvil about which the crumple zone face 127 deforms. In use, the support structure 100 is able to support significant weight pressing downward along the transverse axis 135, such as the weight of a vehicle occupant stepping down on the side step 105. 15 Similarly, the support structure 100 is able to resist significant force pressing upward along the transverse axis 135, such as the force of a rock pressing up against the side step 105 during a four-wheel drive manoeuvre in rough terrain. However, if a significant side force, such as during a vehicle to 20 vehicle side impact, is applied to the distal end 125 of the support structure 100, approximately along the compression axis 130, deformation members 145 of the crumple zone 140 will deform. That can absorb and dissipate some of the energy of a side impact collision. For example, the crumple zone 140 can be tuned to absorb and 25 dissipate energy in a manner similar to the body structure 115 of a vehicle. That can ensure that side impact air bags are not deployed prematurely, but function effectively as intended by the original equipment manufacturer (OEM) of a vehicle. According to some embodiments, a spacer block 150 is positioned 30 between the support structure 100 and the vehicle chassis 110. For example, bolts 155 are used to clamp an attachment end of the frame 107 between the spacer block 150 and a clamping plate 160. The clamping 7 plate 160 also restrains the frame 107 such that any upward force on the distal end applied along the transverse axis 135 places the lower edge of the frame 107, in particular the lower deformation member 145, in tension. An axial element 163 extends axially between the lower and upper 5 ends of the frame 107 and defines an outboard end of the crumple zone 140. The axial element 163 in combination with the frame 107 adds substantial torsional stiffness to the support structure 100. Also, the axial element 163 assists in supporting vertical loading of the support structure 100, yet it is also designed to buckle during side impacts to further absorb 10 side impact crash energy. Further, according to some embodiments of the present invention, a second crumple zone in the form of a tubular element 165 is attached to the distal end 125 of the frame 107. As described in more detail below, the tubular element 165 can also crush during a side impact and absorb 15 and dissipate further crash energy. Those skilled in the art will appreciate that the support structure 100 functions as a bracket extending outward from the side of the body structure 115 of a vehicle. Thus for example two or more support structures 100 can be attached to the chassis 110 between the front and 20 rear wheels (not shown) of the vehicle. The side step 105 and the tubular element 165 then are attached to and extend longitudinally (e.g., into the page in FIG. 1) between the two or more support structures 100. Referring to FIGs. 2A, 2B, 2C, 2D, 2E and 2F, a series of computer generated images illustrate a front view of the sequential deformation of 25 the support structure 100 during a side impact. FIG. 2A illustrates the support structure 100 in an undeformed state, as shown in FIG. 1, before an impact. Next, FIG. 2B illustrates the early deformation of the crumple zone 140 as a crash force, such as applied from a bumper 200 of another vehicle, is applied from left to right at the distal end 125 along the 30 compression axis 130. In particular, note that the lower deformation member 145, which is part of the frame 107, has begun to bend inwards about the spacer block 150.

8 FIG. 2C illustrates the further deformation of the crumple zone 140, as the side impact crash progresses. In particular, a middle deformation member 145 has begun to buckle and bend downwards. That results in the crumple zone 140 moving relative to the attachment end 120 both 5 inwards along the compression axis 130 and downwards along the transverse axis 135, which further absorbs and dissipates crash energy. In particular a portion of the crumple zone face 127 is shown folding over the edge of the spacer block 150. FIG. 2D illustrates still further deformation of the crumple zone 140. 10 The tubular element 165 has also deformed into an oval shape, thus functioning as a second crumple zone that absorbs additional crash energy. Also, a central web section 205, which is welded to the frame 107, remains largely undeformed during the side impact. That enables the 15 central web section 205 to transfer crash energy effectively to the unidirectional crumple zone 140, and to function under normal use as a strong gusset member that supports vertical loads on the side step 105 along the transverse axis 135. FIGs. 2E and 2F illustrate final deformations of the unidirectional 20 crumple zone 140. In particular, the axial element 163 is substantially deformed. Also, note the significant sideways displacement of the distal end 125 that occurs between the undeformed support structure 100 of FIG. 2A and the fully deformed support structure 100 of FIG. 2F. In particular, the crumple zone face 127 is shown folded at more than 90 25 degrees over the edge of the spacer block 150. As will be understood by those having ordinary skill in the art, unidirectional crumple zones according to the present invention can include various different geometries. For example, the crumple zone 140 includes the deformation elements 145 that define a truss structure. Thus, 30 depending on the type of loading applied to the support structure 100, some of the deformation elements 145 will be in tension while other deformation elements 145 will be in compression. For example, the lower 9 deformation element 145, forming part of the frame 107, is placed in tension (and is thus relatively strong) when an upward vertical load is applied to the distal end 125 along the transverse axis 135; but the same lower deformation element 145 deforms under compression (and is thus 5 relatively weak) when a sideways impact load deforms the unidirectional crumple zone 140, as illustrated in FIGs. 2A to 2F. The support structure 100 can be made of various materials, including metal and non-metal elements. For example, the frame 107 can be fabricated from a single piece of bent sheet steel, and other elements 10 are then welded to the frame 107, including the tubular element 165, central web section 205 and crumple zone 140. Other elements such as the side step 105 can be bolted onto the frame 107. Referring to FIG. 3 through FIG. 8, front views are illustrated of support structures 300, 400, 500, 600, 700, 800, according to various 15 alternative embodiments of the present invention. As shown, numerous different types of unidirectional crumple zones can be used. For example, a crumple zone of FIG. 7 includes a transverse channel section 705 that collapses during a side impact crash deformation. Referring to FIG. 9, a front perspective view further illustrates the 20 above described features of the support structure 100. Advantages of the present invention thus include enabling, on a vehicle with a side step, side impact crash forces to be transferred to a vehicle chassis in a manner similar to a vehicle without a side step. That can allow side impact air bag sensors, which are often mounted on a 25 vehicle chassis, to function as designed, regardless of whether a vehicle is equipped with a side step. The skilled in the art will appreciate that the teachings of the present invention also can be applied to other vehicle and non-vehicle components, where a support structure or bracket having a unidirectional crumple zone is required. 30 The above description of various embodiments of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention 10 to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art of the above teaching. Accordingly, while some alternative embodiments have been discussed specifically, other 5 embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. Accordingly, this patent specification is intended to embrace all alternatives, modifications and variations of the present invention that have been discussed herein, and other embodiments that fall within the spirit and scope of the above described invention. 10 Limitations in any patent claims associated with the present disclosure should be interpreted broadly based on the language used in the claims, and such limitations should not be limited to specific examples described herein. In this specification, the terminology "present invention" is used as a reference to one or more aspects within the present 15 disclosure. The terminology "present invention" should not be improperly interpreted as an identification of critical elements, should not be improperly interpreted as applying to all aspects and embodiments, and should not be improperly interpreted as limiting the scope of any patent claims.

Claims (17)

1. A support structure, including: a frame having an attachment end and a distal end, a compression axis extending from the attachment end to the distal end, and a transverse 5 axis substantially orthogonal to the compression axis; a unidirectional crumple zone, attached to the frame between the attachment end and the distal end, defining a crumple zone face substantially orthogonal to the compression axis; and an anvil member covering only a portion of the crumple zone face 10 and having an edge substantially parallel to the crumple zone face; wherein the unidirectional crumple zone is oriented to a) deform under a compressive force applied at the distal end toward the attachment end along the compression axis by folding a portion of the crumple zone face over the edge of the anvil member, and b) resist deformation under a 15 transverse force applied at the distal end along the transverse axis.

2. The support structure of claim 1, wherein the unidirectional crumple zone includes deformation members. 20

3. The support structure of claim 2, wherein at least one of the deformation members is placed in compression under the compressive force and is placed in tension under the transverse force.

4. The support structure of claim 1, wherein the unidirectional crumple 25 zone includes a truss structure.

5. The support structure of claim 1, wherein the support structure is a side step of a vehicle. 30

6. The support structure of claim 1, wherein the attachment end is attached to a frame or chassis of a vehicle. 12

7. The support structure of claim 1, wherein the anvil member comprises a spacer block that is attached to a frame or chassis of a vehicle. 5

8. The support structure of claim 1, wherein the unidirectional crumple zone is oriented to resist deformation under a transverse force applied at the distal end in either direction along the transverse axis.

9. The support structure of claim 1, wherein the attachment end 10 includes a clamping plate.

10. The support structure of claim 1, wherein the attachment end is adjacent to the unidirectional crumple zone. 15

11. The support structure of claim 1, wherein a second crumple zone is attached to the distal end of the frame.

12. The support structure of claim 1, wherein the second crumple zone includes a tubular element. 20

13. The support structure of claim 1, wherein elements of the unidirectional crumple zone move relative to the attachment end along both the compression axis and the transverse axis during deformation of the unidirectional crumple zone under the compressive force. 25

14. The support structure of claim 1, wherein the crumple zone is tuned to match side impact energy absorbing qualities of a vehicle body.

15. The support structure of claim 1, wherein the frame includes bent sheet steel. 30 13

16. The support structure of claim 1, wherein a central web section including at least a part of the unidirectional crumple zone is attached to the frame. 5

17. The support structure of claim 1, wherein the portion of the crumple zone face folds over the edge of the anvil member by approximately 90 degrees.