Design of synchronous motion mechanism and mold for slide block and automatic thread demolding

Abstract

Abstract: According to the structural characteristics of the terminal protection sleeve of an electric power equipment， two sets of motion mechanisms were designed to implement automatic thread demolding. These two mechanisms are a screw rod nut pair driving slider to move in a straight line and a thread core edge rotating in a straight line with the slider. The teeth of the slider gear and thread demolding gear have the same numbers， and their screw rod pitch is the same as that of the thread core. The hydraulic motor can drive the driving gear to rotate， and the driving gear is engaged with the slider gear and thread demolding gear at the same time. This ensures that the slider moves synchronously with the thread demolding without any damage in the plastic part thread. The plastic part of the protective sleeve was made of 30 % glass?fiber-reinforced polybutylene terephthalate （PBT+30 % GF）. During the injection molding， the heat loss of the mold cavity and core should be fast and uniform. The cooling effect of the mold directly influenced the bending deformation of the plastic part. The axial movement of the designed spiral core was driven by the slider， which is advantageous to the design and processing of the cooling water path and the solution of the cooling problem of the threaded core. The mold flow analysis and verification were carried out for the design scheme， which shortened the development period of products and ensured the product quality.

Key words: automatic thread demoulding, synchronous motion, cooling system, mold flow analysis, injection mould

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