关键词: 板材成形, 数控渐进成形, 支撑体, 密闭空间, 通气孔

Abstract: To solve the reaction force inference on forming quality and precision which was generated by continuously compressed air in sealed cavity that was formed between the sheet and support in the CNC incremental negative forming process,a method to automatically generate a support die with vents of triangular mesh model by sheet metal parts CAD model was proposed.The algorithm to calculate empty cavity volume and pressure of support die,to identify the number of concave part on complex sheet parts and to generate a vent in the location of right place automatically which in turn generates a support die with vents of triangular mesh model were introduced.The case studies showed that the proposed algorithm could automatically generate a support die with vents.Sheet forming experiments indicated that the formation of confined spaces in the forming process leaded to a bulge deformation or fracture on sheet parts,but the support die with vents could effectively solve the problems mentioned above.

Key words: sheet forming, CNC incremental forming, support body, confined space, vent