Abstract The present method for the shaping of a metal part comprises the following steps performed with the device according to the invention: A. THE LENGTH OF THE INITIAL BLANK TO BE SHAPED IS SOMEWHAT GREATER THAN THAT DESIRED FOR THE END PRODUCT, WITH SUBSTANTIALLY CONSTANT CROSS-SECTIONAL SURFACE AREAS, BUT WITH TRANSVERSE DIMENSIONS (WIDTH AND THICKNESS) SUCH THAT UPON COMPLETION OF THE FIRST-STEP SHAPING OPERATION THESE LASTMENTIONED DIMENSIONS ARE SLIGHTLY INFERIOR, AT ALL POINTS, TO THOSE OF THE DESIRED PART; B. IN A FIRST STEP, THE SHAPING OPERATION IS PERFORMED BY APPLYING TO THE PART IN A DIRECTION SUBSTANTIALLY PERPENDICULAR TO THE LONGITUDINAL AXIS THEREOF A FORCE SUFFICIENT FOR SHAPING THE PART BETWEEN ONE OR TWO DIES AND ONE OR MORE PUNCHES DEFINING THEREBETWEEN A CAVITY CAPABLE OF PROVIDING THE END SHAPE OF THE PART TO BE OBTAINED AFTER THE LONGITUDINAL ELASTIC RELEASE THEREOF, THE SHAPING STROKE BEING LIMITED BY EXTERNAL STOP MEMBERS; C. IN A SECOND STEP, WITHOUT RELIEVING THE RIGID CLOSING OF SAID CAVITY, THE PART CONTAINED THEREIN IS STABILIZED BY APPLYING TO ONE OR EITHER END OF SAID PART IN THE DIRECTION OF THE AXIS THEREOF, AN UPSETTING FORCE SUFFICIENT TO CAUSE SAID PART TO BE SHORTENED TO A LIMITED EXTENT DETERMINED BY STOP MEANS OR AN ANTAGONISTIC FORCE, AND TO CAUSE THE VERY SLIGHT SWELLING EFFECT RESULTING FROM THE APPLICATION OF SAID UPSETTING FORCE TO BE ABSORBED BY SAID CAVITY, THE UPSETTING STRESS BEING RELIEVED BEFORE OR SIMULTANEOUSLY WITH THE CAVITY CLOSING STRESS.
A method of forming and stress-relieving a sheet-metal blank comprising the steps of: a. pressing a sheet-metal blank, having a length between 1 and 10 percent greater than that of the finished article to be produced, in a die cavity between a pair of dies relatively movable transversely to said blank to bend said blank and apply bending stress thereto, while confining said blank in a die cavity having a width and thickness corresponding to that of said article and slightly exceeding at all points those of said blank by causing said dies to engage respective abutments, at least one edge of said blank projecting laterally from said cavity; and b. pressing a tool into said edge to upset said blank and cause the material thereof to fill said cavity by swelling, thereby relieving said bending stress.
Claim 2
Independent Claim
137 words
A method of forming and stress-relieving a sheet-metal blank comprising the steps of: a. pressing a sheet-metal blank, having a length between 1 and 10 percent greater than that of the finished article to be produced, in a die cavity between a pair of dies relatively movable transversely to said blank to bend said blank and apply bending stress thereto, while confining said blank in a die cavity having a width and thickness corresponding to that of said article and slightly exceeding at all points those of said blank by causing said dies to engage respective abutments, at least one edge of said blank projecting laterally from said cavity; and b. pressing a tool into said edge to upset said blank and cause the material thereof to fill said cavity by swelling, thereby relieving said bending stress.
Claim 3
Independent Claim
177 words
An apparatus for shaping and stress-relieving a sheet-metal blank, comprising: a pair of relatively displaceable dies including at least one movable die shiftable transversely to said blank to bend the latter; means for displacing the movable die transversely to said blank; abutment means for said movable die limiting the displacement thereof to confine said blank in a cavity from which said blank projects at least along one side thereof, said cavity having a thickness and width slightly greater than these of said blank at all points and corresponding to the thickness and width of the article to be produced whereby said blank is maintained under bending stress in said cavity; at least one punch shiftable transversely to said blank and adapted to remove material along a side of said blank, said punch defining said cavity with said dies and said abutment means; and an upsetting tool shiftable laterally of said cavity and engageable with said edge to upset said blank and cause it to swell and fill said cavity while relieving the bending stress of said blank.
Claim 4
Independent Claim
177 words
An apparatus for shaping and stress-relieving a sheet-metal blank, comprising: a pair of relatively displaceable dies including at least one movable die shiftable transversely to said blank to bend the latter; means for displacing the movable die transversely to said blank; abutment means for said movable die limiting the displacement thereof to confine said blank in a cavity from which said blank projects at least along one side thereof, said cavity having a thickness and width slightly greater than these of said blank at all points and corresponding to the thickness and width of the article to be produced whereby said blank is maintained under bending stress in said cavity; at least one punch shiftable transversely to said blank and adapted to remove material along a side of said blank, said punch defining said cavity with said dies and said abutment means; and an upsetting tool shiftable laterally of said cavity and engageable with said edge to upset said blank and cause it to swell and fill said cavity while relieving the bending stress of said blank.