Patent ID: 6922602

Claim:
A method for generating a sheet metal model that can be unfolded automatically, from a solid model obtained by modeling an outer shape of a sheet metal product in a three-dimensional sheet metal CAD/CAM system, the method comprising the steps of: assigning entered attribution information including material and thickness of a sheet metal to a specified solid model; assigning entered designation information for designating an open plane and a bending portion to the solid model; obtaining a minimum radius of curvature at the bending portion from the material and the thickness of the sheet metal; generating a downsized model defined by the designated open plane and a plurality of planes that are generated by moving a plurality of planes of the solid model except the open plane inward in parallel by a distance that is a sum of the thickness of the sheet metal and the minimum radius of curvature; generating inner wall surfaces by moving a plurality of surfaces of the downsized model except for the open plane outward in parallel by a distance that is equal to the minimum radius of curvature; generating plate portions by a projection process in which the inner wall surfaces are further moved outward in parallel by a distance that is equal to the thickness of the sheet metal; and generating a bending portion form that is a fillet connecting neighboring plate portions at the bending portion designated in the solid model.