Multi-ram press and method of metal forming

Abstract

A method of forming a workpiece, including the steps of: providing a center ram, a first outside ram, a second outside ram, and a die; pressing the center rain against the workpiece and toward the die to a first predetermined die depth; trapping the workpiece between the center ram and the die; pressing the first outside ram and the second outside ram against the workpiece and toward the die to a second predetermined die depth; and stretching the workpiece beyond a yield tensile strength of the workpiece material. The die surface has a die center surface which includes at least part of a first arcuate surface, a first planar surface, and at least part of a second arcuate surface. The center ram surface is complimentary in shape to the die center surface.

1 . A method of forming a workpiece, comprising the steps of: 
 providing a center ram, a first outside ram, a second outside ram, and a die, said die including a die surface having a first arcuate surface, a first planar surface and a second arcuate surface, said first planar surface being interposed between said first arcuate surface and said second arcuate surface, said die surface having a die center surface including at least part of said first arcuate surface, said first planar surface, and at least part of said second arcuate surface, said center ram having a center ram surface including a center ram first arcuate surface, a center ram planar surface, and a center ram second arcuate surface, said center ram planar surface being interposed between said center ram first arcuate surface and said center ram second arcuate surface, said center ram surface being complimentary in shape to said die center surface;    pressing said center ram against the workpiece and toward said die to a first predetermined die depth;    trapping the workpiece between said center ram and said die;    pressing said first outside ram and said second outside ram against the workpiece and toward said die to a second predetermined die depth; and    stretching the workpiece beyond a yield tensile strength of the workpiece material using said die, said center ram, said first outside ram and said second outside ram.    
   
   
       2 . The method of  claim 1 , further including the step of forming the workpiece in a shape complimentary to a surface of said die.  
   
   
       3 . The method of  claim 2 , further including the step of eliminating a spring-back in the workpiece.  
   
   
       4 . A forming tool for forming a workpiece, said forming tool comprising: 
 a die including a die surface having a die center surface, a die first outer surface and a die second outer surface, said die center surface in between said die first outer surface and said die second outer surface;    a center ram including a center ram surface complimentary in shape to said die center surface;    a first outside ram including a first outside ram surface complimentary in shape to said die first outer surface; and    a second outside ram including a second outside ram surface complimentary in shape to said die second outer surface.    
   
   
       5 . The forming tool of  claim 4 , wherein said die surface includes a first arcuate surface, a first planar surface and a second arcuate surface, said first planar surface interposed between said first arcuate surface and said second arcuate surface, said die center surface includes at least part of said first arcuate surface, said first planar surface, and at least part of said second arcuate surface.  
   
   
       6 . The forming tool of  claim 5 , wherein said die surface includes a first edge planar surface connected to said first arcuate surface, and a second edge planar surface connected to said second arcuate surface.  
   
   
       7 . The forming tool of  claim 6 , wherein said die surface includes a third edge planar surface extending from said first edge planar surface, and a fourth edge planar surface extending from said second edge planar surface.  
   
   
       8 . The forming tool of  claim 4 , wherein said center ram surface includes a center ram first arcuate surface, a center ram planar surface, and a center ram second arcuate surface, said center ram planar surface interposed between said center ram first arcuate surface and said center ram second arcuate surface.  
   
   
       9 . The forming tool of  claim 8 , wherein said first outside ram surface includes a first outside ram arcuate surface connected to a first outside ram edge surface.  
   
   
       10 . The forming tool of  claim 9 , wherein said second outside ram surface includes a second outside ram arcuate surface connected to a second outside ram edge surface.  
   
   
       11 . A press for forming a workpiece, said press comprising: 
 at least one guidepost;    a forming tool actuatable along said at least one guidepost, said forming tool comprising: 
 a die including a die surface having a die center surface, a die first outer surface and a die second outer surface, said die center surface in between said die first outer surface and said die second outer surface;  
 a center ram including a center ram surface complimentary in shape to said die center surface;  
 a first outside ram including a first outside ram surface complimentary in shape to said die first outer surface; and  
 a second outside ram including a second outside ram surface complimentary in shape to said die second outer surface.  
   
   
   
       12 . The press of  claim 11 , wherein said die surface includes a first arcuate surface, a first planar surface and a second arcuate surface, said first planar surface interposed between said first arcuate surface and said second arcuate surface, said die center surface includes at least part of said first arcuate surface, said first planar surface, and at least part of said second arcuate surface.  
   
   
       13 . The press of  claim 12 , wherein said die surface includes a first edge planar surface connected to said first arcuate surface, and a second edge planar surface connected to said second arcuate surface.  
   
   
       14 . The press of  claim 13 , wherein said die surface includes a third edge planar surface extending from said first edge planar surface, and a fourth edge planar surface extending from said second edge planar surface.  
   
   
       15 . The press of  claim 11 , wherein said center ram surface includes a center ram first arcuate surface, a center ram planar surface, and a center ram second arcuate surface, said center ram planar surface interposed between said center ram first arcuate surface and said center ram second arcuate surface.  
   
   
       16 . The press of  claim 15 , wherein said first outside ram surface includes a first outside ram arcuate surface connected to a first outside ram edge surface.  
   
   
       17 . The press of  claim 16 , wherein said second outside ram surface includes a second outside ram arcuate surface connected to a second outside ram edge surface.