製品設計と型設計の統合最適化による
フライホイールの低パンチ荷重ネットシェイプ加工法

抄録

A small flywheel can be formed directly from a cylindrical workpiece by cold axisymmetric upsetting with lateral extrusion. The authors found that an effective material flow for fulfilling a die cavity in the above die forging can be generated by placing a stepwise cavity on the bottom die plane at the peripheral section. When the dimensions of the hollow plane formed on the disk product by the above die configuration are optimized in the shape and die designs of a flywheel, the net shape forging of a flywheel can be achieved by semi-core forging with the above improved material flow. The advantage of the above forming technology is that no severe increase in punch load, observed in core forging at the final stage of the forming process, occurs, and die life can be elongated in net shape forging. The surface condition and inner strain condition of the product were also investigated by observing the products and FEM, and sufficiently good conditions were confirmed