Patent ID: 8296097

Claim:
An unmoldability determination apparatus comprising: a normal line calculation unit that calculates a normal line extending from a point on a plurality of surfaces constituting a three-dimensional shape of a molded product; an opposite direction component determination unit that determines whether or not the normal line calculated on each surface has an opposite direction component which is a directional component opposite to a mold release direction of a mold of the molded product prescribed for the each surface; a reach determination unit that, when a surface having a point at which the normal line having the opposite direction component is calculated is a projection surface, determines whether or not there is another surface on the molded product which one of a line extending from the projection surface in the mold release direction and a line extending in a direction opposite to the mold release direction reaches; and an unmoldability determination unit that, when there is another surface which both of the line extending from the projection surface in the mold release direction and the line extending in the direction opposite to the mold release direction reaches, determines the projection surface to be unreleasable from the mold only by movement of the mold in the mold release direction, thus determining the projection surface to be unmoldable.