The selection of optimal cooling parameters for the multi-cavity die

The subject of this study is a finite element and abductive network method application for the multi-cavity die. In order to select the optimal cooling system parameters to minimise the warp of a die-casting die, the Taguchis method and the abductive network are used. These methods are applied to create an efficient model with functional nodes for the considered problem. Once the cooling system parameters are developed, this network can be used to predict the warp for the die-casting die accurately. A simulated annealing (SA) optimisation algorithm with a performance index is then applied to the neural network for searching for the optimal cooling system parameters, and obtains a rather satisfactory result as compared with the corresponding finite element verification.     

注塑模数字化设计技术研究

阐述了一种注塑模数字化设计技术.运用Pro/E软件的通用功能模块和模架设计专家(EMX)模块,进行塑件及注塑模设计.以相机面壳注塑模设计为例,验证了该方法的可行性.该方法可以提高塑料注射模具的开发效率.     

气体辅助注射成型数值模拟技术研究概述与展望

在介绍气体辅助注射成型数值模拟技术及其重要性的基础上,对气体辅助注射成型数值模拟技术的国内外研究现状进行了概述,并且对气体辅助注射成型数值模拟技术研究发展方向进行了展望。     

Optimum Gate Design of FreeForm Injection Mould using the Abductive Network

This study uses the injection position and size of the gate as the major control parameters for a simulated injection-mould. Once the injection parameters (gate size and gate position) are given, the product performance (deformation) can be accurately predicted by the abductive network developed. To avoid the numerous influencing factors, first the part-line of the parameter equation is created by an abductive network to limit the range of the gate. The optimal injection parameters can be searched for by a simulation annealing (SA) optimisation algorithm, with a performance index, to obtain a perfect part. The major purpose is searching for the optimal gate location on the part-surface, and minimising the air-trap and deformation after part formation. This study also uses a practical example which has been and proved by experiment to achieve a satisfactory result.     

线圈架注射模设计

介绍了线圈架注射模的设计,模具采用一模两腔结构.介绍了由斜导柱驱动的侧向分型与抽芯机构,以及先复位机构.采用推管和推杆联合作用,实现塑件的脱模.模具结构合理,生产效率较高,并且实现了批量生产,所生产的塑件质量满足要求.     

细长盲孔注射模的创新改进

分析了细长盲孔注射模的结构特点,介绍了细长盲孔注射模的改进思路和具体应用,重点对细长盲孔注射模的浮动型芯设计进行了分析和阐述,对同类注射模具的设计具有参考价值.     

The use of the Petri net reduction approach for an optimal deadlock prevention policy for flexible manufacturing systems

In a flexible manufacturing system (FMS) with multiple products, deadlocks can arise due to limited shared resources, such as machines, robots, buffers, fixtures etc. The development of efficient deadlock prevention policies, which can optimise the use of system resources, while preventing deadlocks from occurring, has long been an important issue to be addressed. In [1], an optimal deadlock prevention policy was proposed, based on the use of reachability graph (RG) analysis of the Petri net model (PNM) of a given FMS and the synthesis of a set of new net elements, namely places with initial marking and related arcs, to be added to the PNM, using the theory of regions. The policy proposed in [1] is optimal in the sense that it allows the maximal use of resources in the system according to the production requirements. For very big PNMs, the reachability graph of the PNMs becomes very large and the necessary computations to obtain an optimal deadlock prevention policy become more difficult. In this paper, we propose the use of the Petri net reduction approach to simplify very big PNMs so as to make necessary calculations easily in order to obtain an optimal deadlock prevention policy for FMSs. An example is provided for illustration.