Hollow section and a process for its manufacture

Abstract

A hollow section made of a metal alloy and having at least one hollow space which is delimited by walls featuring end lengths forming corner regions. The walls exhibit at least in part different thicknesses in cross-section. The thickness of the end length of the walls diminishes in a continuous manner to a smaller thickness. The facing and approximately parallel outer walls of the hollow section are joined on the inside by at least one integral inner wall. The outer walls along with the inner walls delimit a plurality of hollow chambers and the walls of each chamber exhibit in each case a middle length of constant thickness and at both ends thereof an end length of increasing thickness.

1 . A hollow section comprising walls that delimit a hollow space, the walls having end lengths that form corner regions, the end lengths have a cross-sectional thickness that diminishes in a continuous manner to a smaller thickness.  
     
     
         2 . The hollow section according to  claim 1 , wherein the thickness of the end length of one wall of the hollow section is constant over a length starting from a corner region and begins to have a narrowing cross-section at a bottom end point of the length.  
     
     
         3 . The hollow section according to  claim 1 , wherein one wall has a thickness reduced in a constant manner from one corner region to another corner region of the hollow section.  
     
     
         4 . The hollow section according to  claim 2 , wherein the length of the end length of the wall corresponds to one third to one quarter of an overall length of the wall.  
     
     
         5 . The hollow section according to  claim 1 , wherein the end length of one wall which diminishes in cross-sectional thickness from one corner region of the hollow section joins a length of the wall that increases in thickness.  
     
     
         6 . The hollow section according to  claim 5 , wherein the walls include having a wall section with an end length of constant thickness that connects with a transverse wall at one end, and tapers in cross-section to a smaller thickness in a continuous manner starting from an end point of the end length.  
     
     
         7 . The hollow section according to  claim 6 , wherein another transverse wall intersects the wall provided with an end length of constant thickness.  
     
     
         8 . The hollow section according to  claim 1 , wherein each wall of the hollow section has a length of constant thickness in a middle region between two end lengths of diminishing thickness to each other.  
     
     
         9 . The hollow section according to  claim 1 , wherein two facing outer walls of the hollow section are connected on an inner side by at least one integral inner wall.  
     
     
         10 . The hollow section according to  claim 9 , wherein the two facing walls are substantially parallel to each other.  
     
     
         11 . The hollow section according to  claim 9 , wherein the outer walls along with the inner walls delimit a plurality of hollow chambers, the walls of each chamber having a middle part of constant thickness and at both ends of the middle part an end part of increasing thickness.  
     
     
         12 . The hollow section according to  claim 9 , wherein the outer walls define a rectangular cross-section with a center in a region of crossing of a pair of inner walls.  
     
     
         13 . The hollow section according to  claim 11 , wherein the cross-sectional length of the middle part corresponds to approximately double the cross-sectional length of the integral end part.  
     
     
         14 . The hollow section according to  claim 1 , wherein the walls have end parts with a wall thickness that increases in a continuous manner up to the corner region.  
     
     
         15 . The hollow section according to  claim 9 , wherein a wall thickness of an end part of the inner wall increases in a continuous manner up to the outer wall whereby a central plane forms a plane of symmetry.  
     
     
         16 . The hollow section according to  claim 8 , wherein a maximum wall thickness of an end part of a wall is at least 5% greater than a thickness of a part of the wall neighboring the end part of the wall.  
     
     
         17 . The hollow section according to  claim 16 , wherein the maximum wall thickness of the end part is at least 15% greater than the thickness of the neighboring part of the wall.  
     
     
         18 . The hollow wall section according to  claim 17 , wherein the maximum wall thickness of the end part is at least 20% greater than the neighboring part of the wall.  
     
     
         19 . The hollow section according to  claim 8 , wherein a maximum wall thickness of an end part of the wall is at most 200% greater than a thickness of a part of the wall neighboring the end part of the wall.  
     
     
         20 . The hollow section according to  claim 19 , wherein a maximum wall thickness of the end part is at most 100% greater than the thickness of the neighboring part of the wall.  
     
     
         21 . The hollow section according to  claim 20 , wherein a maximum wall thickness of the end part is at most 60% greater than the thickness of the neighboring part of the wall.  
     
     
         22 . The hollow section according to  claim 8 , wherein an average wall thickness of an end part of the wall is at least 5% greater than an average thickness of the wall part neighboring the end part of the wall.  
     
     
         23 . The hollow section according to  claim 22 , wherein the average thickness of the end part is at least 15% greater than the average thickness of the neighboring wall part.  
     
     
         24 . The hollow section according to  claim 23 , wherein the average wall thickness of the end part is at least 20% greater than the average thickness of the neighboring wall part.  
     
     
         25 . The hollow section according to  claim 8 , wherein an average wall thickness of an end part of the wall is at most 200% greater than an average thickness of a part of the wall neighboring the end part of the wall.  
     
     
         26 . The hollow section according to  claim 25 , wherein the average thickness of the en d part is at most 100% greater than the average thickness of the neighboring wall part.  
     
     
         27 . The hollow section according to  claim 26 , wherein the average thickness of the end part is at most 60% greater than the average thickness of the neighboring wall part.  
     
     
         28 . The hollow section according to  claim 8 , wherein the wall thickness of the wall length neighboring the end lengths of the wall is uniform.  
     
     
         29 . The hollow section according to  claim 8 , wherein each wall has an outer face that is flat and a corresponding inner wall face in end regions of the wall has a slope with respect to the outer face which increases the wall thickness.  
     
     
         30 . The hollow section according to  claim 9 , wherein a maximum wall thickness of an end part of a wall is at least 5% greater than a thickness of a part of the wall neighboring the end part of the wall.  
     
     
         31 . The hollow section according to  claim 30 , wherein the maximum wall thickness of the end part is at least 15% greater than the thickness of the neighboring part of the wall.  
     
     
         32 . The hollow wall section according to  claim 31 , wherein the maximum wall thickness of the end part is at least 20% greater than the neighboring part of the wall.  
     
     
         33 . The hollow section according to  claim 9 , wherein a maximum wall thickness of an end part of the wall is at most 200% greater than a thickness of a part of the wall neighboring the end part of the wall.  
     
     
         34 . The hollow section according to  claim 33 , wherein a maximum wall thickness of the end part is at most 100% greater than the thickness of the neighboring part of the wall.  
     
     
         35 . The hollow section according to  claim 34 , wherein a maximum wall thickness of the end part is at most 60% greater than the thickness of the neighboring part of the wall.  
     
     
         36 . The hollow section according to  claim 9 , wherein an average wall thickness of an end part of the wall is at least 5% greater than an average thickness of the wall part neighboring the end part of the wall.  
     
     
         37 . The hollow section according to  claim 36 , wherein the average thickness of the end part is at least 15% greater than the average thickness of the neighboring wall part.  
     
     
         38 . The hollow section according to  claim 37 , wherein the average wall thickness of the end part is at least 20% greater than the average thickness of the neighboring wall part.  
     
     
         39 . The hollow section according to  claim 9 , wherein an average wall thickness of an end part of the wall is at most 200% greater than an average thickness of a part of the wall neighboring the end part of the wall.  
     
     
         40 . The hollow section according to  claim 39 , wherein the average thickness of the en d part is at most 100% greater than the average thickness of the neighboring wall part.  
     
     
         41 . The hollow section according to  claim 40 , wherein the average thickness of the end part is at most 60% greater than the average thickness of the neighboring wall part.  
     
     
         42 . The hollow section according to  claim 9 , wherein the wall thickness of the wall length neighboring the end lengths of the wall is uniform.  
     
     
         43 . The hollow section according to  claim 9 , wherein each wall has an outer face that is flat and a corresponding inner wall face in end regions of the wall has a slope with respect to the outer face which increases the wall thickness.  
     
     
         44 . A process for shape forming a hollow section comprising walls that delimit a hollow space, the walls having end lengths that form corner regions, the end lengths have a cross-sectional thickness that diminishes in a continuous manner to a smaller thickness, comprising the step of deforming the shallow section by creating high internal pressure in an interior of the section by means of a medium capable of flow.