W.S. Sze

Parting Lines and Parting Surfaces of Injection Moulded Parts

This paper presents a computer method for automatic determination of a parting line and the corresponding parting surface of a part for injection moulding. The method requires the input of a solid model of the part and the preferred injection mould parting direction. The outputs are the computed parting line and parting surfaces for the specified parting direction, which would allow the resulting mould halves to be configured. The method also detects interlocking surfaces for the specified parting direction, in which case side cores are required.

An Octree Approach to Rough Machining

This paper presents an octree subdivision based algorithm of automatic cutter path generation for machining on a numerical control machining centre. Both the stock and the part are represented by solid models. The machining strategy is based on a layer by layer approach taking care of the cutter strength and the variation of the part geometry. This approach allows the problem to be reduced from a three-dimensional to a two-dimensional cutter path generation problem which is solved by a quadtree representation of the plane. The method can be easily extended to include the jigs and fixtures and any other obstacles which would be represented by solid models. Algorithms are described in Pascal-like structure.