Reciprocating Die-Assisted Drawing of Shaped Metal Components

Abstract

A drawing unit with a segment reciprocating die for drawing metal segments comprises a tensioning device arranged to advance a shaped specimen through an array of dies that create a shaped orifice with the spacing formed between the dies. These dies segments act under the influence of a powered unit to move in a reciprocating motion that causes the spacings between segments to increase and decrease synchronously thereby shaping the metal segments.

What is claimed is: 
     
         1 . Apparatus for cross sectional reducing and straightening shaped metal segments comprising; an arrangement of reciprocating contact dies, means for delivering reciprocation motion and compressive force to the contact dies, a constraining mechanism to support and guide the contact dies segments, and a tensioning device that provides a tensile loading and axial advancing of a reduced segment exiting the reciprocating contact dies. 
     
     
         2 . Apparatus according to  claim 1 , where a reciprocation travel of the dies is less than the total reduction imparted in a given pass through the dies, in which contact with the die alone limits the rate of piece advancement with each reciprocation and provides uninterrupted axial constraint thereby allowing maintained tension of the exited segments. 
     
     
         3 . Apparatus according to  claim 1 , where a reciprocation travel is greater than the total reduction imparted in a given pass through the dies, in which a device is present to grasp the segment on an entry side of the reciprocating dies to limit rate of the segment advance through the dies and provide uninterrupted back tension 
     
     
         4 . Apparatus according to  claim 1 , where the travel direction of the reciprocating dies intersects at a single point of convergence. 
     
     
         5 . Apparatus according to  claim 1 , where at least one of the travel directions of the reciprocating dies segments does not have a shared intersection with other dies used to reduce a segment. 
     
     
         6 . Apparatus according to  claim 1 , where the means for die reciprocation comprises a powered eccentric shaft attached to the die through a connecting linkage. 
     
     
         7 . Apparatus according to  claim 1 , where the means for die reciprocation is an electromagnetic actuator. 
     
     
         8 . Apparatus according to  claim 1 , where the tensioning device is powered by a pneumatic cylinder to provide continuous tension during reduction through synchronized reciprocating dies. 
     
     
         9 . Apparatus according to  claim 1 , where the tensioning device is powered by a hydraulic cylinder to provide continuous tension during reduction through synchronized reciprocating dies. 
     
     
         10 . Apparatus according to  claim 9 , where an energy storage device is mounted between a grasping mechanism and a hydraulic mechanism to provide tension for the interrupted advance of the segment resulting from cyclic reciprocation of the dies. 
     
     
         11 . Apparatus according to  claim 1 , where the tensioning device is powered by a mechanical linear actuator to provide continuous tension during reduction through synchronized reciprocating dies. 
     
     
         12 . Apparatus according to  claim 11 , where an energy storage device is mounted between a grasping mechanism and a hydraulic mechanism to provide tension for the interrupted advance of the workpiece resulting from cyclic reciprocation of the dies. 
     
     
         13 . Apparatus according to  claim 1 , where the tensioning device is powered by a powered rack and pinion mechanism to provide continuous tension during reduction through synchronized reciprocating dies. 
     
     
         14 . Apparatus according to  claim 13 , where an energy storage device is mounted between a grasping mechanism and a hydraulic mechanism to provide tension for the interrupted advance of the workpiece resulting from cyclic reciprocation of the dies. 
     
     
         15 . Apparatus according to  claim 1 , where a rotation mechanism is mounted between the tensioning device and a grasping mechanism to provide partial rotation in conjunction with axial advance of the segment to mitigate raised seams occurring between the reciprocating die segments. 
     
     
         16 . Apparatus according to  claim 1 , where a mandrel is mounted on an entry side of the reciprocating dies during reduction of tube structures. 
     
     
         17 . Apparatus according to  claim 1 , where reciprocating dies have a second advancement mechanism to open the spacing between dies to enable inhibited feeding of a nose of a workpiece prior to grasping the segment and close to begin reducing the segment. 
     
     
         18 . Apparatus according to  claim 1 , where the constraining mechanism guiding and supporting the reciprocating dies is a sliding journal in an outer supporting frame structure. 
     
     
         19 . Apparatus according to  claim 1 , where the constraining mechanism guiding and supporting the reciprocating die is a pinned connection offset from a reciprocation mechanism mounted to a supporting frame structure. 
     
     
         20 . Apparatus according to  claim 1  wherein the contact dies include an impact surface including two planar surfaces that intersect each other. 
     
     
         21 . A method of shaping a metal segment comprising;
 a) providing at least one pair of reciprocating dies having contact surfaces,   b) advancing the metal segment under tension through a space between the reciprocating dies, and   c) impacting at least two surfaces of the metal segment with the reciprocating dies to shape the metal segment.   
     
     
         22 . The method of  claim 21  wherein the dies travel a distance less than an amount of a reduction in size of the segment in a given pass through the dies. 
     
     
         23 . The method of  claim 21  wherein the dies travels a distance greater than an amount of a reduction in size of the segment in a given pass through the dies and further including the step of grasping the segment on an entry side of the reciprocation dies to limit the rate of segment advance through the dies. 
     
     
         24 . The method of  claim 21  wherein the dies have a contact surface comprising two or more surfaces that intersect each other. 
     
     
         25 . The method of  claim 21  wherein the cycle time of the reciprocating dies and the travel speed of the metal segment is selected based upon the material of the metal segment. 
     
     
         26 . The method of  claim 21  wherein the final shape of the metal segment is determined by the configuration of the contact surfaces of the dies and gaps between the dies.