Automatic generation of venting system on complex surfaces of injection mold

摘要

Building venting system for releasing exhausted air is a very important step in injection mold design. A high-quality venting system can effectively release gas in mold, which will eliminate the defects caused by residual gas and improve the quality of product. However, the surfaces used to create venting system are usually complex, and traditional manual design of venting system is time consuming and difficult to guarantee the design quality on complex surface. To improve the design efficiency and quality of venting system, this paper introduces an automatic approach for designing venting system on complex surfaces of mold. It mainly consists of three steps: (i) original centerline generation, (ii) vent centerline optimization, and (iii) vent channel generation. In step (i), methods of offsetting curves and creating vertical lines on complex surfaces are proposed to generate original vent centerlines. In step (ii), algorithms of connecting curves and curve fairing on complex surfaces are presented to optimize vent centerlines. In step (iii), a hybrid way of extruding and thickening is developed to generate vent features. Based on these three steps, a smooth and continuous venting system can be created on complex surfaces in an automated manner. Finally, a case study with complex surfaces is provided to validate that the design efficiency and quality of venting system can be dramatically improved by using this approach.