Patent ID: 9211579
Filing Date: 2015-12-15
Classification: B21D

Abstract:
1. A method of producing an L-shaped product which includes an L-shaped flat top wall having first and second legs connected to each other so as to define inside and outside edges, an inside wall extending along and connected to the inside edge of the top wall and forming a first angle relative to the top wall, and an outside wall extending along and connected to the outside edge of the top wall and forming a second angle relative to the top wall, each of the inside and outside walls being terminated by a flange substantially parallel to the top wall, the method comprising the steps of: providing a sheet metal material; providing a drawing die assembly; and stamping the sheet metal material with the drawing die assembly to produce an intermediate product which includes an L-shaped flat top wall having first and second legs corresponding to the first and second legs of the L-shaped flat top wall of the completed L-shaped product, and inside and outside walls corresponding to the inside and outside walls of the completed L-shaped product, and flanges corresponding to the flanges of the completed L-shaped product; wherein the intermediate product includes a first region adjacent to a free end of the first leg and an opposite second region adjacent to the second leg, wherein, in the first region, the angle between each of the inside and outside walls relative to the top wall of the intermediate product substantially coincides with the first and second angles of the completed L-shaped product, and wherein, in the second region, the angle between each of the inside and outside walls relative to the top wall gradually increases toward the second leg; the method further comprising the steps of: providing a bending die assembly; stamping the intermediate product by the bending die assembly to produce the completed L-shaped product.