Patent ID: 7650773

Claim:
A method for drawing sheet metal into an edge protector including a bent portion and a pair of planar portions conforming to a leading edge and a pair of lateral sides of a blade to be protected, respectively, the leading edge being given with a three dimensional contour, comprising: press forming a piece of planar sheet metal into a preformed work piece having a U-shaped cross section by using a primary die assembly, the preformed work piece being provided with a bent portion extending along a longitudinal direction and a pair of planar portions extending from either side of the bent portion, the bent portion being given with a contour that conforms to the leading edge of the blade to be protected; preparing a secondary die assembly including a punch including an upper edge portion and a pair of lateral sides conforming to the leading edge and lateral sides of the blade to be protected, respectively, at least a pair of lateral die blocks configured to cooperate with the lateral sides of the punch to shape the planar portions of the preformed work piece so as to conform to the lateral sides of the blade to be protected and an upper clamp member including a recess conforming to an outer contour of the bent portion of the preformed work piece and configured to clamp the bent portion of the preformed work piece in cooperation with the upper edge portion of the punch; placing the preformed work piece onto the punch and clamping the preformed work piece between the upper edge portion of the punch and the recess of the upper clamp member; pushing the lateral die blocks onto the planar portions of the preformed work piece against the corresponding lateral sides of the punch; and opening the secondary die assembly to take out the finally press formed work piece as a finished edge protector.