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On the control of plastic injection molding machine Modern plastic injection molding machine is a set of mechanical, electrical and fluid in one typical system, as this device has forming complex products, less post-processing, processing characteristics of the plastic variety, since its inception has grown rapidly, the current full Over 80% of the worlds products are used plastic injection molding machine for processing.Conventional injection molding machines generally use a simple open-loop control, that is, in accordance with a pre-set value of control. In the device manufacturing process, pre-configured parameter values, such as the clamping force, cycle time, temperature, etc., from the machine in the production process be maintained. For example, by controlling the die temperature can be maintained the temperature of heating fluid, plastic temperature can be outside the heating device by controlling the power to maintain. This control method of simple structure, however, poor anti-interference ability to control the temperature is relatively low.At present, more injection molding machine uses a closed-loop control, that is, according to on-line measurement value and set the value of the deviation control. Closed-loop control system uses a negative feedback loop, anti-jamming ability, when the injection speed, injection pressure, mold cavity temperature, cavity pressure, melt temperature and oil pressure due to interference in the production process, deviation of the machine through the adaptive control system for automatic correction of interference. This control method of anti-interference ability, high control accuracy. More advanced control method is to apply computer controlled, that is, to build a closed-loop real-time computer control system. It includes direct digital control system (DDC), supervisory computer control system (SCC), distributed control system (DCS) and multi-level control of several types.Commonly used injection molding machine control system has three kinds, namely, the traditional relay-based, programmable controllers and computer-based control type. In recent years, programmable logic controller (referred to as PLC) with its high reliability, high-performance characteristics in injection molding machine control system has been widely used. In order to improve the level of injection molding machine control system and quality, a higher level than the PLC, control system design specifically for small and medium programmable computer controller (PCC) came into being. PCC integrates a standard PLC and industrial control computer features, multi-task time-sharing operating systems, data computing and processing power more powerful than the PLC. PCC formed with injection molding machine control system in order to achieve, including position control, speed control, temperature control, fault control and real-time display the whole process such as injection molding a variety of control can greatly improve the quality of plastic products will help enhance economic benefits.Control of the contents of the injection molding machineInjection molding machine process control system mainly consists of two parts: First, the temperature control system in order to right barrel, melt and mold temperature control; second motion control system to the process of injection pressure, velocity and displacement multiple class switching.In the temperature control, its control accuracy has reached a 1 . Precise temperature control in precision injection molding that help improve product quality and availability of raw materials is a very important indicator. In the plastic processing, temperature control include barrel, nozzle and mold temperature control. Barrel temperature of the barrel surface heating temperature, due to relatively thick wall barrel, so the choice of thermocouple detection point is critical, and different test points on the temperature curve is a large difference. Therefore, parallel detection of double-point, namely, surface and deep in the barrel at the same time set the thermocouples, will be relatively stable temperature curve is conducive to temperature control accuracy. Nozzle melt temperature directly affects the passage of the shear flow, the quality of the products have a major impact, so the nozzle temperature control precision demanding. Mold temperature is in contact with the product mold cavity surface temperature, it will significantly affect the charge membrane, cooling and packing process. For the mold temperature control method can be used control the heat carrier temperature method can also directly control the mold temperature. In the former approach, in order to heat the temperature for the control of the export vector objects, is relatively simple and can meet the general temperature control requirements. When the temperature control precision is high generally use the second method of temperature control.Injection speed, packing pressure, back pressure is the injection of part of the sol to control the first of the three variables directly affect the accuracy of its control product quality. Modern more advanced injection molding machine equipped with 5-10 multi-stage injection speed and packing, as well as melt glue back pressure control. Generally through displacement / velocity sensors, pressure sensors, closed-loop injection control, and high response servo valves used in conjunction to achieve the process of injection molding melt glue back pressure, injection speed and packing conditions of precise control. Another relatively simple approach is to use closed-loop proportional valve, through the proportional valve spool position of their own closed-loop control to improve control precision. However, spool position is an intermediate variable, so the control accuracy somewhat less.Transfer mold process control variable is the main clamping force, clamping force and time again is stable and the necessary conditions for forming the cycle. Transfer mode control of the process should be another important variable is location. On the one hand, advanced injection molding machine constant pursuit of efficiency, directly affect the speed of transfer mold molding cycle, and quickly transfer to the deceleration control mode in itself has put forward higher requirements. On the other hand, due to special process of continuous development and promotion of position control precision molds have become increasingly demanding.PLC and PCCSince the late 20th century, 60 the United States the first programmable logic controller PLC inception, PLC control technology has gone through a 30-year development process, especially with modern computer technology and microelectronics technology, it has been in the soft hardware technology is far out of the original sequence control of the prototype stage. Programmable Computer Controller (PCC) is to represent the development trend of this new generation of programmable controllers.PLC compared with conventional, PCC is a for motion control, process control and network control of dedicated control system, is a standard PLC, numerical control systems and industrial performance characteristics of the computer in one of the intelligent controller. PCC is its biggest feature is similar to a large computer time-sharing multi-tasking operating systems and diverse software applications design. Most of the conventional single-task PLC clock scanning or monitoring procedures to deal with the process itself of the logic operation instructions and external I / O channel status of collection and refresh. This treatment led directly to control the speed, depends on the size of the application, this result is no doubt that I / O channels in real-time control of the high demand religions. PCCs system software the perfect solution to this problem, it uses time-sharing mechanism to build their applications multi-tasking software operating platform, so that the application program running the length of cycle and has nothing to do, but by the decision cycle of the operating system. As a result, it will scan cycle of the application with the real distinction between the external control cycle to meet the real requirements of real-time control. Of course, this control cycle in the CPU computing power to allow the premise, according to the users actual requirements, arbitrary changes.PCC application modules from the multi-task structure, the development of application software to the project has brought great convenience. Because it can easily control the project in accordance with the various parts of the different functional requirements, such as motion control, data acquisition, alarm, PID regulator computing, communications, control, namely the preparation of a control program module (task), these modules not only operate independently, the data between one another to maintain a certain interrelated, these modules through the step by step after the independence of the development and debugging can be downloaded to the PCC along with the CPU, in the regulation and management of multi-tasking operating systems run in parallel under the joint realization of the project control requirements.PCC a single task in the preparation of the different modules with a flexible choice of the characteristics of different programming languages, which means that not only in conventional PLC has been to people familiar ladder, instruction list language can continue to be used on the PCC, but users can be used more efficient and intuitive high-level language (PL2000), which is a complete text for the control of language, BASIC technical personnel familiar with the syntax it will feel a kind of deja vu, which control requirements for the description of a very simple, intuitive. In addition, PCCs application software development also has an integrated C language program capacity, thus providing powerful data computing and processing power.On the hardware structure, PCC is characterized by very significant. In its core computing module inside, PCC for its CPU is equipped with multiple conventional PLC, mass storage unit (100K/16M), this is undoubtedly a powerful system and application software provides a hardware-based monitoring. PCC on the hardware features, but also reflected in its various signals for industrial site designed many dedicated interface module, such as the high-frequency pulses, incremental encoder, temperature, weighing signal and ultrasonic signal interface module. They will all forms of on-site signal is very convenient to PCC joint into the core of the digital control system, the user may need to use the systems hardware I / O channels in a single road, road, or dozens of way more than a decade as a unit module carried out dozens of point-to-hundreds of thousands of point-point expansion and networking.PCC in the industrial control powerful advantages, and demonstrate the programmable controllers and industrial control computers and DCS (Distributed Industrial Control System) technology, the development trend of convergence, although this is still a relatively young technology, but in its more come more and more application areas, it is increasingly demonstrating its potential for development can not be underestimated. For the injection molding machine, the current widespread application of the PLC control system, but as technology advances, personalized, customized products, growing demand for injection molding machine control requirements more complex, higher and higher precision, PCC as a more advanced control system, will gradually occupy a certain market share. On the other hand, for the future network-based production requirements, obviously, PCC control system more competitive edge, so we have reason to believe, PCC control system will be in the future take place in the field of injection molding machines.This information comes from 【Wishsino Plastic Injection Molding Company Website】 对注塑机的控制现代塑料注塑机是一个典型的系统集机械，电气和流体，此设备已形成了复杂的产品，少的后处理，加工各种塑料的特性，自成立以来发展迅速，目前全过世界上的产品80用于加工塑料注塑成型机。传统的注塑机一般采用简单的开环控制，即按照预先设定值的控制。 在设备制造过程中，预先设定的参数值，如从机器的锁模力，循环时间，温度等，在生产过程中予以保留。 例如，通过控制模具温度可以维持加热流体的温度，塑料温度可控制电源，以保持外加热装置。 这种结构简单的控制方法，然而，穷人的抗干扰能力，控制温度也比较低。目前，更多的注塑机采用闭环控制，即根据上线的测量值和设定值的偏差控制。 闭环控制系统采用了负反馈回路，抗干扰能力强，当注射速度，注射压力，模腔温度，模腔压力，熔体温度和压力油，由于干扰，在生产过程中通过机器的偏差自适应控制系统的干扰进行自动修正。 这一控制方法抗干扰能力强，控制精度高。 更先进的控制方法是应用计算机控制，就是建立一个闭环实时计算机控制系统。 它包括直接数字控制系统（DDC），监督计算机控制系统（SCC），分布式控制系统（DCS）和多层次的几种类型的控制。常用的注塑机控制系统有三种，即传统的基于继电器，可编程控制器和基于计算机的控制类型。 近年来，可编程逻辑控制器（简称为PLC）以其高可靠性，高性能的特点在注塑机控制系统已被广泛使用。 为了提高注塑机控制系统和质量水平更高的水平，比PLC控制系统的设计专门为中小型可编程计算机控制器（PCC）的应运而生。 政协集成了一个标准的PLC和工业控制计算机的功能，多任务分时操作系统，数据计算和处理能力比PLC更强大。 政协形成了注塑机控制系统，以实现包括位置控制，速度控制，温度控制，故障控制和实时显示整个过程中，如注塑成型的各种控制，可以大大提高塑料制品的质量有利于提高经济效益。控制注塑机的内容注塑机过程控制系统主要由两部分组成：一是温度控制系统，为了权利桶，熔体和模具的温度控制;第二项议案注射压力，速度和位移的多级交换过程的控制系统。在温度控制，其控制精度达到了1。 在精密注塑精确的温度控制，有助于提高产品质量和原料的可用性是非常重要的指标。 在塑料加工中，温度控制主要包括料筒，喷嘴和模具的温度控制。 料筒温度，料筒表面加热温度，由于料筒的壁比较厚，因此热电偶检测点的选择是至关重要的，在不同的温度曲线测试点是一个很大的区别。 因此，双点，即表面，在同一时间在每桶深平行检测设置热电偶，将是相对稳定的温度曲线，有利于温度控制精度。 喷嘴熔融温度直接影响剪切流的推移，产品的质量有重要影响，因此喷嘴温度的控制精度要求。 模具温度是在接触与产品模具型腔表面温度，它会显着影响充膜，冷却和包装过程。 对于模具温度控制方法可用于控制热载体温度的方法也可以直接控制模具温度。 前一种方法中，以加热载体的出口对象的控制温度，相对简单，并能满足一般的温度控制要求。 当温度控制精度高，一般使用温度控制的第二种方法。注射速度，保压压力，背压是注射部分溶胶控制的三个变量直接影响其控制产品质量的准确性。 现代更先进的注塑机配备5-10多级注射速度和包装，以及熔胶背压控制。 一般通过位移/速度传感器，压力传感器，闭环注射控制，高响应伺服阀配合使用，实现注塑成型工艺，熔胶背压，注射速度和精确控制的条件下包装。 另一种比较简单的方法是采用闭环比例阀，通过比例阀阀芯自己的闭环控制的位置，以提高控制精度。 然而，阀芯位置是一个中间变量，因此控制精度稍差。传输模过程控制变量是主要的锁模力，锁模力和时间，又是稳定的成型周期的必要条件。 传输模式控制过程应该是另一个重要的变量是位置。 一方面，先进的注塑机不断追求效率，直接影响转移模具成型周期的速度，并迅速转移本身的减速控制模式提出了更高的要求。 另一方面，由于特殊工艺的不断发展和推广的位置控制精密模具的要求越来越高。PLC与PCC自20世纪后期以来，60，美国第一台可编程逻辑控制器PLC以来，PLC控制技术已走过了30年的发展过程，尤其是与现代计算机技术和微电子技术，在软，硬件技术已远远出原来的“顺序控制”的原型阶段。 可编程计算机控制器（PCC）就是代表这新一代可编程控制器的发展趋势。与传统的PLC相比，PCC是一种用于运动控制，过程控制和网络控制的专用控制系统，是一个标准PLC，数控系统和工业计算机的性能于一体的智能控制器的特点。 PCC是其最大的特点是类似于大型计算机的分时多任务操作系统和多样化的应用软件的设计。 最传统的单任务的PLC时钟扫描或监控程序处理过程本身的逻辑运算指令和外部I / O通道的状态收集和刷新。 这种待遇，直接导致“控制速度”，在应用程序的大小取决于，这个结果是毫无疑问的高要求宗教在实时控制I / O通道。 PCC的系统软件的完美解决方案这个问题，它采用分时机制构建自己的应用程序多任务的软件操作平台，使应用程序运行周期的长短和无关，但是，在决策周期操作系统。 作为一个结果，它会扫描应用的周期同真正外部的控制周期之间的区别，以满足实时控制的实际需求。 当然，这在控制循环的CPU运算能力允许的前提下，根据用户的实际要求，任意更改。PCC的应用程序模块，从多任务结构，应用软件开发项目带来了极大的便利。 因为它可以很容易地控制项目按照不同的功能要求的各个部分，如运动控制，数据采集，报警，PID调节运算，通信，控制，即编制的控制程序模块（任务），这些模块不仅独立运作，彼此之间的数据，以保持一定的相互关联的步骤，通过这些模块后，独立开发和调试的步骤可以下载到该委员会与CPU一起，在调控和管理多并行运行任务操作系统下，共同实现项目的控制要求。宝成单个任务在不同的模块准备，用不同的编程语言，这意味着不仅在常规PLC一直到人们熟悉的阶梯的特点灵活选择，指令表语言委员会可以继续使用，但用户可以使用更加高效和直观的高级语言（PL2000），这是一个完整的文字语言控制，基本熟悉语法的技术人员会感到一种似曾相识的感觉，这说明控制要求一个非常简单的，直观的。 此外，PCC的应用软件的开发还具有集成“C”语言程序的能力，从而提供了强大的数据计算和处理能力。在硬件结构，PCC的特点非常显着。 在其核心计算模块内部，PCC为其CPU配备有多个传统的PLC，大容量存储单元（100K/16M），这无疑是一个强大的系统和应用软件提供了基于硬件的监控。 PCC的硬件功能，而且还体现在各种信号设计了许多专用的接口模块，如高频脉冲，增量式编码器，温度，称重信号及超声波信号接口模块为工业用地，。 他们将各种形式的现场信号是很方便的到宝成联合成数字控制系统的核心，用户可能需要将系统的硬件I / O通道在一个单一的道路，道路或几十方法比十年作为一个单元模块进行了成千上万的点对点的扩大和网络点至数百数十家。PCC在工业控制中强大的优势，并展示了可编程控制器与工业控制计算机及DCS（分布式工业控制系统）技术，融合的发展趋势，虽然这仍然是一个相对年轻的技术，但在其多来越来越多的应用领域，它正日益显示出其发展潜力不可低估。 注塑机，目前的PLC控制系统的广泛应用，但随着技术的进步，个性化，定制产品，注塑机的控制要求的日益增长的需求更加复杂，精度高，宝成更先进的控制系统，将逐步占据一定的市场份额。 另一方面，为未来的网络为基础的生产要求，显然，PCC控制系统更具竞争优势，所以我们有理由相信，PCC控制系统在未来将是发生在注塑机领域。
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