Process for forming a variable gauge metal sheet into a desired shape

1. A process for forming a variable gauge metal sheet into a desired shape, said process comprising:

providing a variable gauge metal sheet having a first surface and a second surface along a longitudinal direction, the metal sheet having a thickness measured at any point on the metal sheet as a distance between the first surface and the second surface, the thickness of the metal sheet being different over a first portion of the sheet than over a second portion of the sheet along a transverse direction, and

forming said metal sheet into a first desired shape by bending the metal sheet about a first fold line, said first fold line extending through both the first portion and the second portion, to bring segments of the first surface of the metal sheet on either side of the first fold line into increased opposition with each other,

wherein said bending of the metal sheet about the first fold line is effected by holding the metal sheet on a first clamped side of the first fold line secured between a first clamping die and a second clamping die while applying forces to the second surface of the metal sheet on a second moved side of the first fold line,

wherein the first clamping die has a first engagement surface which engages the first surface of the metal sheet and is a complementary mirror image to a surface contour of the first surface of the metal sheet that it engages,

wherein the second clamping die has a second engagement surface which engages the second surface of the metal sheet and is a complementary mirror image to a surface contour of the second surface of the metal sheet that it engages.

2. The process according to claim 1 , wherein said bending of the metal sheet about the first fold line urges the first surface of the metal sheet on the second moved side of the first fold line into a first stationary die block, said first stationary die block having a first engagement surface which engages the first surface of the metal sheet and is a complementary mirror image to the surface contour of the first surface of the metal sheet.

3. The process according to claim 2 , wherein a second moving die block is moved into engagement with the second surface of the metal sheet on the second moved side of the first fold line to urge the first surface of the metal sheet on the second moved side of the first fold line into the first stationary die block,

the second moving die block having a second engagement surface which engages the second surface of the metal sheet and is a complementary mirror image to the surface contour of the second surface of the metal sheet into which it is urged.

4. The process according to claim 3 , wherein the second surface of the metal sheet has a surface contour which is a flat planar surface throughout the substantial entirety of the second surface in the same flat plane on either side of the first fold line before said bending.

5. The process according to claim 4 , wherein the first fold line lies in the second surface of the metal sheet spaced away from the first surface of the metal sheet.

6. The process according to claim 1 , wherein the bending of the sheet metal about the first fold line is effected by wing bending.

7. The process according to claim 1 , wherein the first fold line extends along the metal sheet from a first end of the metal sheet to a second end of the metal sheet, with a central plane intermediate the ends of the metal sheet and normal to the first fold line, the thickness of the metal sheet being substantially symmetrical along the central plane.

8. The process according to claim 1 , further comprising forming said metal sheet into a second desired shape by bending the metal sheet about a second fold line, said second fold line extending through both the first portion and the second portion to bring segments of the first surface of the metal sheet on either side of the second fold line into increased opposition with each other,

wherein said bending of the metal sheet about the second fold line is effected by holding the metal sheet on a first clamped side of the second fold line secured between a third clamping die and a fourth clamping die while applying forces to the second surface of the metal sheet on a second moved side of the second fold line,

the third clamping die having a first engagement surface which engages the first surface of the metal sheet and is a complementary mirror image to the surface contour of the first surface of the metal sheet that it engages,

the fourth clamping die having a second engagement surface which engages the second surface of the metal sheet and is a complementary mirror image to the surface contour of the second surface of the metal sheet that it engages.

9. The process according to claim 8 , wherein said bending of the metal sheet about the second fold line urges the first surface of the metal sheet on the second moved side of the second fold line into a third stationary die block, said third stationary die block having a first engagement surface which engages the first surface of the metal sheet and is a complementary mirror image to the surface contour of the first surface of the metal sheet.

10. The process according to claim 9 , wherein a fourth moving die block is moved into engagement with the second surface of the metal sheet on the second moved side of the second fold line to urge the first surface of the metal sheet on the second moved side of the second fold line into the third stationary die block, the fourth moving die block having a second engagement surface which engages the second surface of the metal sheet and is a complementary mirror image to the surface contour of the second surface of the metal sheet into which it is urged.

11. The process according to claim 10 , wherein the process is used to form an automotive component comprising an elongate tie bar for a radiator assembly having a U-shape in end view and with the first fold line and the second fold line extending longitudinally of the elongate tie bar.

12. The process according to claim 9 , wherein the process is used to form an automotive component comprising an elongate tie bar for a radiator assembly having a U-shape in end view and with the first fold line and the second fold line extending longitudinally of the elongate tie bar.

13. The process according to claim 8 , further comprising forming said metal sheet into a third desired shape by bending the metal sheet about a third fold line, said third fold line extending through both the first portion and the second portion to bring segments of the first surface of the metal sheet on either side of the third fold line into increased opposition with each other,

wherein said bending of the metal sheet about the third fold line is effected by holding the metal sheet on a first clamped side of the third fold line secured between a fifth clamping die and a sixth clamping die while applying forces to the second surface of the metal sheet on a second moved side of the third fold line,

the fifth clamping die having a first engagement surface which engages the first surface of the metal sheet and is a complementary mirror image to the surface contour of the first surface of the metal sheet that it engages,

the sixth clamping die having a second engagement surface which engages the second surface of the metal sheet and is a complementary mirror image to the surface contour of the second surface of the metal sheet that it engages.

14. The process according to claim 13 , wherein said bending of the metal sheet about the third fold line urges the first surface of the metal sheet on the second moved side of the third fold line into a fifth stationary die block, said fifth stationary die block having a first engagement surface which engages the first surface of the metal sheet and is a complementary mirror image to the surface contour of the first surface of the metal sheet.

15. The process according to claim 14 , wherein a sixth moving die block is moved into engagement with the second surface of the metal sheet on the second moved side of the third fold line urge the first surface of the metal sheet on the second moved side Of the third fold line into the fifth stationary die block,

the sixth moving die block having a second engagement surface which engages the second surface of the metal sheet and is a complementary mirror image to the surface contour of the second surface of the metal sheet into which it is urged.

16. The process according to claim 14 , wherein the process is used to form an automotive component comprising an elongate tie bar for a radiator support assembly having a tubular shape in end view and with the first fold line, the second fold line and the third fold line extending longitudinally of the elongate tie bar.

17. The process according to claim 13 , wherein said third desired shape is a hollow tube.

18. The process according to claim 17 , wherein the process is used to form an automotive component comprising an elongate tie bar for a radiator support assembly having a tubular shape in end view and with the first fold line, the second fold line and the third fold line extending longitudinally of the elongate tie bar.

19. The process according claim 13 , wherein the process is used to form an automotive component comprising an elongate tie bar for a radiator support assembly having a tubular shape in end view and with the first fold line, the second fold line and the third fold line extending longitudinally of the elongate tie bar.

20. The process according to claim 8 , wherein the process is used to form an automotive component comprising an elongate tie bar for a radiator assembly having a U-shape in end view and with the first fold line and the second fold line extending longitudinally of the elongate tie bar.