Modelling, design and implementation of a servoelectric plunger mechanism for glass container forming machines

GT V43 2002 89-94

Within the scope of increasing the reliability, the controllability and the speed of glass container forming machines and thus improving the related forming process, servo-electric drives are increasingly replacing pneumatically driven mechanisms that still represent the standard in IS machines today. This contribution discusses the design and the results of an experimental unit
of a fully functional servo-electric plunger mechanism that has been developed by Emhart Glass SA. Since the control of the parison pressing action needs to satisfy a variety of different challenging demands, a thorough understanding of the system is indispensable, and therefore a physical model of the servo-drive and of the glass forming process has been developed. It allows one to
simulate the complete system in virtual reality and to iteratively optimise the electromechanical device, as well as the control algorithm. Trials with the experimental unit that has been built based on the theoretical results confirm that the accuracy of the models is remarkable. Extensive field tests were successfully carried out at Wiegand Glas, Germany, in a real production environment.
The encouraging results demonstrate the high potential regarding reliability, controllability of the forming process, performance and customer benefit of a servoelectric plunger mechanism.