Patent attributes
An object of the present invention is to provide a three-dimensional CAD-system for adding data about a drafting direction of a die to three-dimensional data about the part to be formed by that die, and a cost calculation system for calculating the cost of the part based on that drafting direction data. A three-dimensional model generation unit of a CAD system generates: a three-dimensional shaped model of a given part based on information coming from an input operation unit. A drafting direction data setting unit establishes drafting direction data when the input operation unit is operated to designate the drafting direction of the die for press molding, injection molding or the like of the part in question. A projected area calculation unit calculates a projected area S of the part on a plane perpendicular to the drafting direction of the applicable die on the basis of the three-dimensional model of that part and the drafting direction data involved. A depth calculation unit calculates a depth D of the part in the relevant drafting direction.