Draw-form for exhaust components and method of manufacture
Exhaust tubes comprise tubular structures having draw-forms formed therein so as to provide a flat portion where a HEGO boss (Heated Exhaust Gas Oxygen) can be welded for placement of the HEGO sensor. In such circumstances, it is, therefore, useful that such draw-forms have substantially flat portions. The present invention provides a tubular member having an outer wall, and a draw-form formed in the outer wall. The draw-form comprises a substantially flat bottom portion, a plurality of walls extending upwardly from the bottom portion and attached to the outer wall, and wherein the walls are configured in a polygonal orientation.
1 . A tubular member comprising:
an outer wall; and
a draw-form formed in said outer wall, said draw-form comprising:
a substantially flat bottom portion;
a plurality of walls extending upwardly from said bottom portion and attached to said outer wall; and
wherein said walls are configured in a polygonal orientation.
2 . The tubular member of claim 1 , wherein said draw-form further includes an aperture extending through said bottom portion.
3 . The tubular member of claim 2 , wherein said walls have substantially rounded corners.
4 . The tubular member of claim 3 , wherein said walls are integrally formed with said bottom potion.
5 . The tubular member of claim 4 , wherein said polygonal configuration is a rectangular configuration.
6 . The tubular member of claim 4 , wherein said polygonal configuration is a square configuration.
7 . The tubular member of claim 3 , wherein polygonal configuration of said walls substantially prevent deformation of said draw-form during subsequent forming operations.
8 . The tubular member of claim 7 , wherein said bottom portion remains substantially free from deformation during subsequent forming operations.
9 . The tubular member of claim 7 , wherein said subsequent forming operations includes swaging said tubular member.
10 . The tubular member of claim 1 , wherein said walls are substantially perpendicular to said bottom portion.
11 . An exhaust tube comprising:
a tube having an outer wall defining an interior exhaust passage;
a draw-form formed in said outer wall, said draw-form comprising:
a substantially flat bottom portion;
a plurality of walls extending upwardly from said bottom portion and integrally attached to said outer wall; and
wherein said walls are configured in a polygonal orientation to substantially prevent deformation of said draw-form during subsequent forming operations.
12 . The exhaust tube of claim 11 , further including an aperture extending through said bottom portion.
13 . The exhaust tube of claim 12 , wherein said walls have substantially rounded corners.
14 . The exhaust tube of claim 13 , wherein said polygonal configuration is a rectangular configuration.
15 . The exhaust tube of claim 13 , wherein said polygonal configuration is a square configuration.
16 . The exhaust tube of claim 13 , wherein said rounded corners act as strengthening ridges.
17 . The exhaust tube of claim 16 , wherein said bottom portion remains substantially free from deformation during subsequent forming operations.
18 . The exhaust tube of claim 17 , further comprising a heated exhaust gas oxygen boss inserted into said draw-form, wherein said heated exhaust gas oxygen boss includes projections for assisting in attaching said heated exhaust gas oxygen boss to said draw-form.
19 . The exhaust tube of claim 18 , further comprising a heated exhaust gas oxygen sensor inserted into said heated exhaust gas oxygen boss.
20 . The exhaust tube of claim 19 , wherein said subsequent forming operations includes swaging said tubular member.
21 . A method of manufacturing a draw-form, said method comprising:
placing a tubular member having an outer wall in a fixture;
forming a substantially flat bottom portion in said outer wall of said tube;
forming a plurality of walls extending upwardly from said bottom portion and attached to said outer wall, wherein said walls are configured in a polygonal orientation to maintain said bottom portion substantially free from deformation during subsequent forming operations.
22 . The method of claim 21 , further comprising swaging said tube wherein deformation of said draw-form is substantially prevented.
23 . The method of claim 22 , wherein said walls have rounded corners that act as strengthening ridges.
24 . The method of claim 23 , wherein said polygonal configuration comprises a rectangular configuration.
25 . The method of claim 23 , wherein said polygonal configuration comprises a square configuration.
26 . The method of claim 25 , wherein forming said substantially flat bottom portion is formed by a stamp.
27 . The method of claim 26 , wherein said substantially flat bottom portion, said walls, and said aperture are formed by a single operation.