Research On Temperature Monitoring And Control System Of Hot Pressing Molding Equipment

Precision glass lens processing method is consstantly innovating,the traditional glass lens processing adopts several times of grinding and cutting,which is of low efficiency and various processes,especially in the non-spherical mirror machining and manufacturing,the cost is very expensive.Hot-pressing molding processing of precision glass lens just need only one molding and easy to implement mass production,lower costs and will not pollute the environment,the precision of the surface and shape are controlled by mold profile,which can realize various type surface lens of glass processing.Moulded product quality mainly depends on the quality of the accuracy and stability of temperature monitoring and control system of the equipment,therefore,it is of great realistic significance on the study of temperature control system.This paper mainly studies a set of hot-pressing furnace temperature monitoring and control system with good capability of heat preservation,which can heat the ware in the center of hot-pressing furnace up to 600 ? or so and the insulation precision in + /-1 ?,at the same time,designs the hot-pressing furnace temperature curve,processing flow,main circuit,wiring layout,software setting-up and conducts the experiment to verify the reliability of the design of temperature control system.Conceptual design of hot-pressing furnace is supposed to design base on the investigation of various types of materials,structural style and related research.The temperature control processing curve of hot-pressing molding equipment from warming----insulation----the cooling of the whole process are simulated after all kinds of related hot-pressing furnace parameter is selected,formulating the strict temperature control processing curve,which theoretically determines the change tendency and the reasonable scope of the template temperature at each stage and provides a reliable basis for the processing flow and application programming.On the basis of the simulation,working out the flow chart of every stage of the temperature control system according to the design of temperature control curve and each phase change of temperature,setting each action based on programming logicsequence,makeing every effort to simplify the operation action and make sure that the control system is compact and efficient.Based on the comprehensive analysis of structure,principle and manufacturing technique of extrusion molding equipment temperature control system,as well as the comparison of the mainstream of PLC brands on the market,the OMRON company's CPM2 A PLC is finally selected as the host system,integration module,integrated three-phase voltage regulator module SCR and integrated temperature transmitter SBW,are adopted to design the PLC host control system of hot-pressing molding equipment with two work modes of manual and automatic.We need to design the main circuit and wiring layout of hot-pressing molding equipment temperature control system,as well as the part of software setting-up of PLC control system,which make the control parameter setting and the adjustment of the empirical data is more convenient,modify online and shortening the period of the implementation of control strategy can be also come true.Finally,we built an experimental platform aiming to test temperature performance of hot-pressing furnace which has been processed and assembled.For the test,we use a K type thermocouple to get real-time temperature measurement of the down-pressing template center,and use the infrared thermal imager to measure the temperature change of temperature control points on the top side.In the simulation model,we find the experimental and simulation data maintain in consistency without seal ring,but adding the seal ring,the experimental and simulation data appear larger differences and the seal ring beyond its safe temperature.As a result,the next step,on the one hand,we need to work on material and parameters of seal for further research,on the other hand,take measures to solve the problem of seal temperature being too high.