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外文翻译：Adaptive system for electrically driven thermoregulation of moulds for injection moulding1. Introduction, definition of problem Development of technology of cooling moulds via thermoelectrical (TEM) means derives out of the industrial praxis and problems, i.e. at design, tool making and exploitation of tools.Current cooling technologies have technological limitations.Their limitations can be located and predicted in advance with finite element analyses (FEA) simulation packages but not completely avoided. Results of a diverse state of the art analyses revealed that all existing cooling systems do not provide controllable heat transfer capabilities adequate to fit into demanding technological windows of current polymer processing technologies. Polymer processing is nowadays limited (in term of shortening the production cycle time and within that reducing costs) only with heat capacity manipulation capabilities. Other production optimization capabilities are already driven to mechanical and polymer processing limitations.1.1. Thermal processes in injection moulding plastic processing Plastic processing is based on heat transfer between plastic material and mould cavity. Within calculation of heat transfer one should consider two major facts: first is all used energy which is based on first law of thermodynamicslaw of energy conservation , second is velocity of heat transfer. Basic task at heat transfer analyses is temperature calculation over time and its distribution inside studied system. That last depends on velocity of heat transfer between the system and surroundings and velocity of heat transfer inside the system. Heat transfer can be based as heat conduction, convection and radiation .1.2. Cooling time Complete injection moulding process cycle comprises of mould closing phase, injection of melt into cavity, packing pressure phase for compensating shrinkage effect, cooling phase, mould opening phase and part ejection phase. In most cases, the longest time of all phases described above is cooling time. Cooling time in injection moulding process is defined as time needed to cool down the plastic part down to ejection temperature. The main aim of a cooling process is to lower additional cooling time which is theoretically needless; in praxis, it extends from 45 up to 67% of the whole cycle time. From literature and experiments, it can be seen, that the mould temperature has enormous influence on the ejection time and therefore the cooling time (costs). Injection moulding process is a cyclic process where mould temperature varies as shown in Fig. 1 where temperature varies from average value through whole cycle time.2. Cooling technology for plastic injection moulds As it was already described, there are already several different technologies, enabling the users to cool the moulds. The most conventional is the method with the drilling technology, i.e. producing holes in the mould. Through these holes (cooling lines), the cooling media is flowing, removing the generated and accumulated heat from the mould. It is also very convenient to build in different materials, with different thermal conductivity with the aim to enhance control over temperature conditions in the mould. Such approaches are so called passive approaches towards the mould temperature control. The challenging task is to make an active system, which can alter the thermal conditions, regarding to the desired aspects, like product quality or cycles time. One of such approaches is integrating thermal electrical modules (TEM), which can alter the thermal conditions in the mould, regarding the desired properties. With such approach, the one can control the heat transfer with the time and space variable, what means, that the temperature can be regulated throughout the injection moulding cycle, independent of the position in the mould. The heat control is done by the control unit, where the input variables are received from the manual input or the input from the injection moulding simulation.With the output values, the control unit monitors the TEM module behaviour.2.1. Thermoelectric modules (TEM) For the needs of the thermal manipulation, the TEM module was integrated into mould. Interaction between the heat and electrical variables for heat exchange is based on the Peltier effect. The phenomenon of Peltier effect is well known, but it was until now never used in the injection moulding applications. TEM module (see Fig. 2) is a device composed of properly arranged pairs of P and N type semiconductors that are positioned between two ceramic plates forming the hot and the cold thermoelectriccooler sites. Power of a heat transfer can be easily controlled through the magnitude and the polarity of the supplied electric current.2.2. Application for mould cooling The main idea of the application is inserting TEM module into walls of the mould cavity serving as a primary heat transfer unit. Such basic assembly can be seen in Fig. 3. Secondary heat transfer is realized via conventional fluid cooling system that allows heat flows in and out from mould cavity thermodynamic system. Device presented in Fig. 3 comprises of thermoelectric modules (A) that enable primarily heat transfer from or to temperature controllable surface of mould cavity (B). Secondary heat transfer is enabled via cooling channels (C) that deliver constant temperature conditions inside the mould. Thermoelectric modules (A) operate as heat pump and as such manipulate with heat derived to or from the mould by fluid cooling system (C). System for secondary heat manipulation with cooling channels work as heat exchanger. To reduce heat capacity of controllable area thermal insulation (D) is installed between the mould cavity (F) and the mould structure plates (E). Fig. 3. The whole application consists of TEM modules, a temperature sensor and an electronic unit that controls the complete system. The system is described in Fig. 4 and comprises of an input unit (input interface) and a supply unit (unit for electronicand power electronic supplyH bridge unit). The input and supply units with the temperature sensor loop information are attached to a control unit that acts as an execution unit trying to impose predefined temperate/time/position relations. Using the Peltier effect, the unit can be used for heating or cooling purposes. The secondary heat removal is realized via fluid cooling media seen as heat exchanger in Fig. 4. That unit is based on current cooling technologies and serves as a sink or a source of a heat. This enables complete control of processes in terms of temperature, time and position through the whole cycle. Furthermore, it allows various temperature/time/position profiles within the cycle also for starting and ending procedures. Described technology can be used for various industrial and research purposes where precise temperature/time/position control is required. The presented systems in Figs. 3 and 4 were analysed from the theoretical, as well as the practical point of view. The theoretical aspect was analysed by the FEM simulations, while the practical one by the development and the implementation of the prototype into real application testing.3. FEM analysis of mould cooling Current development of designing moulds for injection moulding comprises of several phases . Among them is also design and optimization of a cooling system. This is nowadays performed by simulations using customized FEM packages (Moldflow ) that can predict cooling system capabilities and especially its influence on plastic.With such simulations, mould designers gather information on product rheology and deformation due to shrinkage as ell as production time cycle information. This thermal information is usually accurate but can still be unreliable in cases of insufficient rheological material information. For the high quality input for the thermal regulation of TEM, it is needed to get a picture about the temperature distribution during the cycle time and throughout the mould surface and throughout the mould thickness. Therefore, different process simulations are needed.3.1. Physical model, FEM analysis Implementation of FEM analyses into development project was done due to authors long experiences with such packages and possibility to perform different test in the virtual environment. Whole prototype cooling system was designed in FEMenvironment (see Fig. 5) through which temperature distribution in each part of prototype cooling system and contacts between them were explored. For simulating physical properties inside a developed prototype, a simulation model was constructed using COMSOL Multiphysics software. Result was a FEM model identical to real prototype (see Fig. 7) through which it was possible to compare and evaluate results. FEM model was explored in term of heat transfer physics taking into account two heat sources: a water exchanger with fluid physics and a thermoelectric module with heat transfer physics (only conduction and convectionwas analysed, radiation was ignored due to low relative temperature and therefore low impact on temperature). Boundary conditions for FEM analyses were set with the goal to achieve identical working conditions as in real testing. Surrounding air and the water exchanger were set at stable temperature of 20 C.Fig. 6. Temperature distribution according to FEM analysis. Fig. 7. Prototype in real environment. Results of the FEM analysis can be seen in Fig. 6, i.e. Temperature distributi through the simulation area shown in Fig. 5. Fig. 6 represents steady state analysis which was very accurate in comparison to prototype tests. In order to simulate the time response also the transient simulation was performed, showing very positive results for future work. It was possible to achieve a temperature difference of 200 C in a short period of time (5 s), what could cause several problems in the TEM structure. Those problems were solved by several solutions, such as adequate mounting, choosing appropriate TEM material and applying intelligent electronic regulation.3.2. Laboratory testing As it was already described, the prototype was produced and tested (see Fig. 7). The results are showing, that the set assumptions were confirmed. With the TEM module it is possible to control the temperature distribution on different parts of themould throughout the cycle time. With the laboratory tests, it was proven, that the heat manipulation can be practically regulated with TEM modules. The test were made in the laboratory, simulating the real industrial environment, with the injectionmoulding machine Krauss Maffei KM 60 C, temperature sensors, infrared cameras and the prototype TEM modules. The temperature response in 1.8 s varied form +5 up to 80 C, what represents a wide area for the heat control within the injection moulding cycle.4. Conclusions Use of thermoelectric module with its straightforward connection between the input and output relations represents a milestone in cooling applications. Its introduction into moulds for injection moulding with its problematic cooling construction and problematic processing of precise and high quality plastic parts represents high expectations. The authors were assuming that the use of the Peltier effect can be used for the temperature control in moulds for injection moulding.With the approach based on the simulation work and the real production of laboratory equipment proved, the assumptions were confirmed. Simulation results showed a wide area of possible application of TEM module in the injection moulding process. With mentioned functionality of a temperature profile across cycle time, injection moulding process can be fully controlled. Industrial problems, such as uniform cooling of problematic A class surfaces and its consequence of plastic part appearance can be solved. Problems of filling thin long walls can be solved with overheating some surfaces at injection time. Furthermore, with such application control over rheological properties of plastic materials can be gained. With the proper thermal regulation of TEM it was possible even to control the melt flow in the mould, during the filling stage of the mould cavity. This is done with the appropriate temperature distribution of the mould (higher temperature on the thin walled parts of the product). With the application of TEM module, it is possible to significantly reduce the cycle time in the injection moulding process. The limits of possible time reduction lies in the frame of 1025% of additional cooling time, describe in Section 1.2 .With the application of TEM module it is possible to actively control the warping of the product and to regulate the amount of product warpage in the way to achieve required product tolerances. The presented TEM module cooling application for injection moulding process is a matter of priority note for the patent, held and owned by TECOS.注塑模具之电力驱动温度调节系统材料加工技术杂志187188 (2007) 6906931、 文章的定义和介绍通过热电（TEM）手段冷却模具技术的发展，派生出的工业实践和问题，即在设计，制作工具和开发工具之中形成。当前的冷却技术有技术上的限制，通过有限元分析模拟包的提前预测可以发现这些局限，但是不能够完全避免。各种不同的分析结果显示，现在所有的冷却系统不能够提供可控制的传热能力，而足以适应目前聚合物加工工艺要求的技术窗口。当前聚合物的加工是在热容量处理能力上被限制的（从生产周期和降低成本上看）。其他生产优化功能几经突破了机械和聚合物加工的限制。1.1.注射成型塑料加工中的热处理工艺塑料加工是以塑件材料和模具型腔之间的热量转移为基础的，在热传递的计算中应该考虑两个主要事实：第一是所有使用的能源应该遵循能量守恒的热力学第一定律，第二个是传热速度。热传递分析的基本任务是随着时间的推移和在被研究系统内部的温度分布计算。最后取决于系统和环境之间、系统内部之间的热量传递速率。塑料加工产生的热量可以通过热传导、对流和辐射进行传递。1.2.冷却时间完整的注塑成型工艺周期包括合模阶段，熔体注入型腔阶段，保持压力补偿收缩效果阶段，冷却阶段，开模阶段和部分弹射阶段。在大多数情况下，以上所描述的所有阶段中，所需时间最长的是冷却阶段。在注塑过程中，冷却时间定义为塑料部件的温度降到可以被弹射出时而所需要的时间。冷却过程的主要目的是为了降低额外的冷却时间，但这在理论上是没有必要的，在实际生产中，冷却时间会在整个生产周期中由45%增加到67%。从大量的文献和实验中可知，模具自身的温度对于模具的排出时间，尤其是冷却时间有巨大的影响。模具注塑成型过程是一个循环的过程中，模具温度变化如图1所示，由图可看出模具温度的变化跨过整个生产周期的平均值。二、注塑模具的冷却技术由于作了一些说明，现在已经有几个不同的冷却技术，这样可以帮助厂家冷却模具。最常用的冷却方法就是钻孔技术，即在模具上钻出一些空。通过这些小孔（冷线），流动的冷却介质可以从模具中带走注塑时产生和积累的热量。这些小孔同样可以很方便的钻在不同的材料上，为了增强对模具温度的控制，应使用不同于模具材料热传导率的冷却介质。因此这种调控温度的方法对于模具的温度控制来说是被动的。做出一个主动调节温度的系统，即可以改变热量状况，从而得到期望的方面，例如产品质量或周期时间，而这是一个具有挑战性的任务。这种做法之一就是整合热电气模块(TEM),他可以改变模具热量条件，从而得到理想的模具特性。用这种方法，可以在时间变量和空间变量下控制热量传递，这就意味着，模具温度可以通过注塑周期来被调节，而不受模具自身各部位的影响。热量控制可以通过控制单元完成，控制单元中的输入变量可由人工输入或注塑模拟输入而被接收。在有输出值的情况下，控制单元可以监视TEM模块的运行状况。2.1.热电模块（TEM) 因为热量控制的需要，热电模块被集成到模具之中。热变量和电气变量之间的相互作用来改变热量是基于珀耳帖效应，珀耳帖效应的现象众周所知的，但它到现在为止从未在注塑应用中使用过。TEM模块是一种位于两个陶瓷板之间的合理布置的几套P型和N型半导体构成的装置，从而形成冷的和热的电势点。热量传递的功率易于被提供电流的大小和极性来控制。2.2.模具冷却的应用 该应用的主要目的是将TEM模块插入模具型腔的内壁中来作为一个主要的热量传递装置。由图3可以看出热电模块的基本装配，通过常规的液体冷却系统，使热流量通过模腔热力系统以实现二次换热。在图3中，该装置由热电模块（A)组成，它可以将大部分热量传递到温度可以被控制的模具型腔的表面上(B)。经过冷却通道（C)以实现二次传热，这样可以使模具内部温度保持不变。热电模块(A)作为热力泵来运转，这样可以通过流体冷却系统(C)来控制热量在模具内导入或导出。整个系统是在冷却通道下进行二次热量控制的热转换工作。为了减少热容量可控区域，绝缘体(D)被安装在模腔(F)和模具结构板(E)之间。整个应用包括温度模块，温度传感器和一个控制整个系统的电子装置。这个系统描述如图4所示，其中包括输入单元（输入接口）和应用单元（电子单元和电力电子供应，即H桥单元）。温度传感器的循环信息的输入和供应单元都连接到一个控制单元 ，其作为一种执行元件试图加强预先确定的温度/时间/位置关系。应用珀尔帖效应 ，这个执行元件可以用于加热或冷却。通过流体冷却介质，二次热量的消除可以实现，由图4的热量转换可以看出。该执行单元是基于目前的冷却技术，并作为一个散热器或热源来使用。这使得在温度，时间和位置方面的整个循环过程中实现完全控制成为可能。此外，它允许在循环过程中不同温度/时间/位置结构可以开始和停止进程。以上所叙述的工艺可以用于那些要求精确控制温度/时间/位置的不同产业和科研之中。图3和图4所展现的系统是从理论和实际的关点来分析的。理论方面是通过有限元模拟分析的，而实践方面是将元件通过真实环境应用程序测试来实现并发展起来的。三、模具冷却的有限元分析目前注塑模具设计的发展，包括几个阶段。其中也包括冷却系统的设
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