Design of Double Internal Thread Demoulding Mechanism and Injection Mould for Cap with Double Layer Different Type Threads
Hu Hengyu, Gao Jin, Pang Jianjun
School of Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou 310018, China
Abstract：A double-layer thread demoulding mechanism and its mould for the cover were designed. The central hole of the cover is divided into upper layer with trapezoid internal thread feature and lower layer with fine internal thread feature. Mould layout is one mould and one cavity, two plate single opening. A non-standard modified mould base was used without ejector plate mechanism. In order to ensure the coaxiality of the upper and lower thread cores, a special single guide pillar was used in the mould base guide mechanism, and single guide pillar guide mechanism matched with double guide bush was designed in both the fixed mould plate and the moving mould plate. The submarine gate was adopted in the mould cavity gating so as to remove waste runer automatically. Aimed at the demoulding of the upper trapezoidal thread, the oil cylinder was used to drive the rack for driving the inner thread core to rotate, and the rotation was controlled by the thread guide sleeve. In view of the demoulding of the lower fine thread, the motor was used to drive the thread core to rotate to realize the demoulding of the thread. The reasonable structure, reliable action and good molding effect of the thread demoulding mechanism can provide useful reference for the injection production of similar plastic parts and reduce the potential design risk.
Keywords：injection mould; thread core-pulling; demoulding; mechanism design; mould design
Hu Hengyu，Gao Jin，Pang Jianjun. Design of double internal thread demoulding mechanism and injection mould for cap with double layer different type threads[J]. Engineering Plastics Application，2020，48(5)：93-97，102.