Automotive crush tip and method of manufacturing

Abstract

Various structural features can be formed in the blank prior to welding opposing walls of a blank together to form a tubular member and/or can be formed simultaneously with forming a wall of the tubular wall. Transverse collapse initiating features can be formed by expanding the material of the wall. These features can be located in a corner portion that connects two side wall portions of the tubular member together and/or in a side wall portion thereof. In cases where both are provided, the side wall and corner collapse initiating features can be aligned with each other. Another portion of the wall material can be free of strain hardening and/or material thinning. A blank for the tubular member can be formed from sub-blanks welded together, can have non-parallel opposing side edges, and/or can have different thickness and/or different material portions.

1 . An automotive crush tip comprising: 
 a tubular member having a longitudinal weld seam joining the opposing side edges of an integral blank together;    a plurality of transverse collapse initiating features located in the tubular member;    wherein at least a portion of the material of the integral blank and the tubular member has not been strain hardened.    
   
   
       2 . An automotive crush tip according to  claim 1 , wherein another portion of the integral blank and the tubular member resulting therefrom has been strain hardened.  
   
   
       3  An automotive crush tip according to  claim 1 , wherein a cross-section of the tubular member varies along a length of the tubular member.  
   
   
       4 . An automotive crush tip according to  claim 1 , wherein the integral blank and the tubular member resulting therefrom has a portion that has one of a thickness, a material and a combination thereof, that is different from another portion of the integral blank.  
   
   
       5 . An automotive crush tip according to  claim 1 , wherein the integral blank and resulting tubular member is constructed of at least two sub-blanks welded together.  
   
   
       6 . An automotive crush tip according to  claim 1 , wherein the tubular member further comprises an attachment feature formed therein.  
   
   
       7 . An automotive crush tip according to  claim 6 , wherein the attachment feature is selected from the group consisting of a hole, a flange and a combination thereof.  
   
   
       8 . An automotive crush tip according to  claim 1 , wherein the plurality of transverse collapse initiating features include a substantially transversely aligned boundary.  
   
   
       9 . An automotive crush tip according to  claim 1 , wherein the plurality of transverse collapse initiating features are selected from the group consisting of a depression, a projection, and a combination thereof.  
   
   
       10 . An automotive crush tip according to  claim 9 , wherein the plurality of transverse collapse initiating features include a substantially transversely aligned boundary.  
   
   
       11 . An automotive crush tip comprising: 
 a tubular member having at least two side wall portions connected together by a corner portion that is straight;    wherein at least one of the at least two side wall portions has an expanded material portion adjacent the straight corner portion.    
   
   
       12 . An automotive crush tip according to  claim 11 , further comprising an unexpanded material portion located in any side wall portion defined by the tubular member.  
   
   
       13 . An automotive crush tip according to  claim 11 , wherein the expanded material portion has a boundary that is substantially transverse to a longitudinal axis of the tubular member.  
   
   
       14 . An automotive crush tip according to  claim 13 , further comprising a collapse initiating feature substantially aligned with the boundary of the expanded portion.  
   
   
       15 . An automotive crush tip according to  claim 11 , further comprising a collapse initiating feature located in the straight corner portion.  
   
   
       16 . An automotive crush tip according to  claim 11 , wherein the tubular member has a cross-section that varies along the length of the tubular member.  
   
   
       17 . An automotive crush tip according to  claim 11 , wherein tubular member has a longitudinal butt weld seam joining together opposing side edges of a blank having a portion that has one of a thickness, a material and a combination thereof, that is different from another portion of the blank.  
   
   
       18 . An automotive crush tip according to  claim 11 , wherein the tubular member has a longitudinal butt weld seam joining together opposing side edges of a blank that is constructed of at least two sub-blanks welded together.  
   
   
       19 . An automotive crush tip according to  claim 16 , wherein the expanded material portion is a transverse collapse initiating feature having a boundary that is substantially transverse to a longitudinal axis of the tubular member.  
   
   
       20 . An automotive crush tip according to  claim 19 , further comprising an additional expanded material portion forming an additional collapse initiating feature located in the straight corner portion and substantially aligned with the substantially transverse boundary.  
   
   
       21 . An automotive crush tip comprising: 
 a tubular member having at least one expanded wall area including a wall thickness that has been thinned, and the tubular member having at least one unexpanded wall area including a wall thickness that has not been thinned.    
   
   
       22 . An automotive crush tip according to  claim 21 , wherein the tubular member has a cross-section that varies along the length of the tubular member.  
   
   
       23 . An automotive crush tip according to  claim 21 , wherein tubular member has a longitudinal butt weld seam joining together opposing side edges of a blank having a portion that has one of a thickness, a material and a combination thereof, that is different from another portion of the blank.  
   
   
       24 . An automotive crush tip according to  claim 23 , wherein the blank is constructed of at least two sub-blanks welded together.  
   
   
       25 . An automotive crush tip according to  claim 21 , wherein the expanded wall area is a transverse collapse initiating feature.  
   
   
       26 . An automotive crush tip according to  claim 21 , wherein the expanded wall area has a boundary that is substantially transverse to a longitudinal axis of the tubular member.  
   
   
       27 . An automotive crush tip according to  claim 21 , wherein the tubular member further comprises a corner portion including an additional expanded wall area including a wall thickness that has been thinned.  
   
   
       28 . An automotive crush tip according to  claim 22 , wherein the additional expanded wall area is a transverse collapse initiating feature.  
   
   
       29 . An automotive crush tip according to  claim 28 , wherein the expanded wall area is a transverse collapse initiating feature and wherein at least one of the expanded wall area and the additional expanded wall area has a boundary that is substantially transverse to a longitudinal axis of the tubular member and that is substantially aligned with the other of the expanded wall area and the additional expanded wall area.  
   
   
       30 . An automotive crush tip according to  claim 29 , wherein the tubular member has a cross-section that varies along the length of the tubular member.  
   
   
       31 . A method useful for manufacturing an automotive crush tip, comprising: 
 forming a blank having opposing longitudinal side edges;    forming the blank into a substantially tubular member wherein the opposing longitudinal side edges are adjacent each other;    welding the opposing longitudinal side edges of the blank together;    forming at least one structural feature in the blank prior to welding the opposing longitudinal side edges together.    
   
   
       32 . A method useful for manufacturing an automotive crush tip according to  claim 31 , wherein forming the blank further comprises forming opposing longitudinal side corner portions that are not parallel with each other.  
   
   
       33 . A method useful for manufacturing an automotive crush tip according to  claim 31 , wherein forming the blank further comprises welding at least two sub-blanks together.  
   
   
       34 . A method useful for manufacturing an automotive crush tip according to  claim 31 , wherein forming the blank further comprises providing a portion of the blank with one of a material, a thickness and a combination thereof that is different from another portion of the blank.  
   
   
       35 . A method useful for manufacturing an automotive crush tip according to  claim 31 , wherein forming at least one structural feature comprises forming one of a transverse collapse initiating feature, an attachment feature, and a combination thereof.  
   
   
       36 . A method useful for manufacturing an automotive crush tip according to  claim 31 , wherein forming the blank into a shape of a substantially tubular member comprises forming a substantially straight corner portion between two side wall portions of the substantially tubular member.  
   
   
       37 . A method useful for manufacturing an automotive crush tip according to  claim 36 , wherein forming the at least one structural member comprises forming a collapse initiating feature in the substantially straight edge.  
   
   
       38 . A method useful for manufacturing an automotive crush tip according to  claim 36 , wherein forming the at least one structural member comprises forming a collapse initiating feature in at least one of the two side wall portions of the substantially tubular member.  
   
   
       39 . A method useful for manufacturing an automotive crush tip according to  claim 37 , wherein forming the at least one structural member comprises forming a collapse initiating feature in at least one of the two side wall portions of the substantially tubular member.  
   
   
       40 . A method useful for manufacturing an automotive crush tip according to  claim 39 , wherein forming the blank further comprises forming opposing longitudinal side edge segments that are not parallel with each other.  
   
   
       41 . A method useful for manufacturing an automotive crush tip, comprising: 
 forming a substantially flat blank having opposing side edges;    forming the substantially flat blank into a wall having a partially tubular shape;    forming the wall into a substantially tubular shape wherein the opposing side edges are adjacent to each other;    welding the opposing side edges together to form the wall into a tubular shape; and    forming at least one structural feature in the wall simultaneously with at least one of forming a substantially flat blank, forming a partially tubular wall, and forming a substantially tubular wall.    
   
   
       42 . A method useful for manufacturing an automotive crush tip according to  claim 41 , wherein forming at least one structural feature comprises forming an attachment feature, a transverse collapse initiating feature, and a combination thereof.  
   
   
       43 . A method useful for manufacturing an automotive crush tip according to  claim 42 , wherein forming at least one structural feature comprises forming a transverse collapse initiating feature in one of a depression, a protrusion, and a combination thereof.  
   
   
       44 . A method useful for manufacturing an automotive crush tip according to  claim 43 , wherein the at least one structural feature is located in a corner portion located between two side wall portions of the wall.  
   
   
       45 . A method useful for manufacturing an automotive crush tip according to  claim 43 , wherein the at least one structural feature is located in a side wall portion of the wall.  
   
   
       46 . A method useful for manufacturing an automotive crush tip according to  claim 45 , wherein at least one additional structural feature is located in a corner portion located between two side wall portions of the wall.  
   
   
       47 . A method useful for manufacturing an automotive crush tip according to  claim 41 , wherein forming the substantially flat blank comprises providing one of the opposing longitudinal side edges with a portion that is not parallel to the other of the opposing longitudinal side edges.  
   
   
       48 . A method useful for manufacturing an automotive crush tip according to  claim 41 , further comprising forming the substantially flat blank from at least two sub-blanks welded together.  
   
   
       49 . A method useful for manufacturing an automotive crush tip according to  claim 41 , wherein forming the substantially flat blank comprises providing a portion of the blank having one of a material, a thickness, and a combination thereof, that is different from another portion of the blank.  
   
   
       50 . A method useful for manufacturing an automotive crush tip according to  claim 49 , wherein forming the blank further comprises forming opposing longitudinal side edge segments that are not parallel with each other.